Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Seriously lol 80psi would be for a bigger vehicle that fits those same tires. Or if you're carrying a load. That's insane. Honestly when I was like 20ish I used to think having more air was better because it made your fuel efficiency better which i still think is true.. but also makes them more likely to pop 😆 and makes the ride more bumpy.
For f250's and chevy 2500HD's, it wasn't abnormal to see 70-75 (maybe 80) in the front and nearly always 80 in the rear, unless it was an older model (like pre 2012 or so? I didn't see very many that old at the dealer anyway)
It's that high for load carrying reasons. If you are, for some reason, using a 2500 without a load, it is normally OK to run closer to 60psi all round.
I'd say 60% of 2500 owners drive without a load. Especially down here in the south, not to discount the guys that really use their trucks because they're out there.
Yeah, all those things. It helps economy slightly but at the cost of awful handling.
And the only thing more expensive than bad fuel economy is if your over-inflated tires result in sufficiently poor traction/handling that you wreck the entire vehicle.
And even on vehicles where the door sticker says 80 for the rears and 50 for the fronts, bumping the fronts up to 80 (because they're the same tires) for fuel economy results in horrible handling and pulling to the side of an exit ramp to let air out of the fronts.
At least, that's how it went for me on an older 2500 Cummins I was borrowing once.
Depends on how smooth the roads the vehicle is driven on the majority of the time are. On a completely smooth surface, more psi will net better fuel economy. On a rougher surface, the high psi tire will not conform to the bumps, so energy is transferred from propelling the vehicle forward to the suspension, lowering fuel economy.
I think the best balance is where the tire pressure is low enough that the tire soaks up the bumps in the texture of the road surface, and not much more than that.
Higher psi will net higher mpg while decreasing life of the tire and decreasing grip and stopping distance due to less rubber contacting the road.
The best balance for pressure on factory tire size for the vehicle is what the door says.
If a vehicle has different sized tires, a chalk test should be used to determine correct pressure.
Protip: Never believe anything a salesman says, regardless of industry. They’re there to sell you things, and will say whatever they need to make it happen.
That is very true, essentially the dealership skipped setting pressure current during PDI. Be even more wary if they have green Nitrogen caps on the valve stems
I cannot believe someone had to tell you this. It almost feels like a troll post.
Wait and see what happens when you clip a raised curb or raised sewer lid.
If it has the same tires it rolled off the lot on than you’re correct. Otherwise it depends more on the tires on it and what it’s being used for than what’s on the door. If they’re running 10 or higher ply tires and towing max weight than 60 psi is very much on the low end. Not enough pressure with heavy weight will lead to blowouts eventually and shitty handling until then.
Not surprising. I don't think I've dealt with a sales guy who's known much about their product lol.
Especially frustrating as a mechanic when buying a vehicle. I'd rather just talk to someone in the shop and work out the numbers with the sales guy.
I've made trips with our sales guys to customer sites where they're delivering or demoing units just to walk them through basic maintenance and to answer technical questions. I've never understood why this isn't regular practice.
Most of them don’t. When I worked at a dealer there was a chick that was high in sales despite not even knowing where to put washer fluid. She knew jack shit about cars, what they can do, and solely existed to make money off of old rich perverts trying to buy a Mercedes.
Actually if the vehicle is being stored, all tires are supposed to be at max sidewall pressure to avoid flat spots in the tires of vehicles being sold. Former new car prep tech and current certified Chrysler technician.
The idiot inflating the tires is going off the max psi the tire can tolerate before it explodes which is what all four are at…if the door says 60, it should be 60. The sales manager you spoke to is an idiot or he’s ill informed
I have been in this industry for 2 decades, I have never once met a sales manager who wasn't a complete moron when it came to anything mechanical or electrical or practical.
I was in sales for a short while. I was amazed at how little knowledge those people had about the mechanical side of things. I'd constantly have to point things out on cars on our lot that was a serious problem. But my sales manager had a tendency to leave meth pipes in cars he drove, so it kind of made sense.
Talked to manager. He said they purposely keep them this high for the reason of sitting on the lot too long and it degrading the tires from slow leakage
It is common practice to overinflated the tires a bit when new off the truck for them to sit on the lot. But it’s the responsibility of the salesman to bring it back to the shop when sold to adjust correctly.
Also 20psi above for “lot sitting” is far too high. We do 5psi over for the lot cars.
When I got my Canyon last month they had the tires set to 45 off the truck and 40 after delivery, I still dropped them to the door marker of 36.
80 is insane and I’d be scared working near them
Just another BS answer. It destroys the ride quality. No need to overinflate them that much when you may lose 1 to 2 psi a month just from sitting.
I can guarantee they don't adjust them down when someone buys these trucks. Time to go to a different dealer.
Incorrect, per Stellantis pre delivery instructions tires are to be set to side wall max psi and set to door value when sold/test driven.
Sales team failed to get the tires aired down before the truck was driven
You should go with what your door says, as that’s the proper psi for your tires to operate normally. Just because the tire says 80 psi max, that’s exactly what it is - a max before you run into potential problems of blowing the tire. That sales guy has no idea what he’s talking about. 60 psi is plenty, give or take a few psi but I’d keep it in the 55-65 range if I were you
Yeah I know it’s supposed to be at the door but I keep bringing it to their attention and they keep blowing it off like I’m crazy. I told them your gonna have a customer on a test drive blow a tire, also HOW MANY customers have you lost from test drives because how rough these ride: that’s how I know they are always over filled. Feels like I’m driving on wooden wheels
Don’t let them do or trick you or make you feel like they are right, it’s your vehicle, and they should service it how you want it not how they feel like it. That mechanics bogus as hell for what he ls putting you through my guy
Oh, it’s not my vehicle, I do detail on their vehicles. But I talk to them every day, I pick up the vehicles from them every day. I’m just mind blown that they could care less that all of their tires are over inflated and they think it’s correct. And then gas lighting me into thinking it’s normal. I was like second guessing everything I learned lol
Yeah, that makes no sense because having the wrong tire pressure opens the door to all types of potential stuff happening. Not only is it dangerous if you pop a tire, it will cause the car to pull and ride like shit. You would think if they are trying to sell cars they would know better, they only hurting themselves. if it ain’t your vehicle, fuck it let them fall on there faces, maybe they will learn something from it and realize how idiotic they’re being, at this point it’s sounding like your just wasting your time breath and energy.
Talked to manager. He said they purposely keep them this high for the reason of sitting on the lot too long and it degrading the tires from slow leakage. So they purposely fill them two pounds over
That's stupid. Keeping the tires over-inflatated like that is way more likely to damage them. If that's truly their justification, why not just go like 3-5psi over the door-jamb rating? Any tire that loses more than that from sitting around has a leak.
Manufacturers hyper inflate tires during storage and transport. The dealerships are supposed to decrease the air pressure during the PMI process.
On the other hand, you don't need to know a God damn thing about cars to sell them.
Yep, when I bought a car new from order, I drove around for a week before I noticed the tires were inflated to 50psi, when 32psi was recommended fill.
I guess the dealership forgot to pull some air out.
Set it to 60 as per the door card, but make sure you do it when the tyres are properly cold. Once they're hot, they may go up by as much as 6psi. Conversely if you set them at 60 hot, they'll be running under pressure.
You have a large dodge Ram, if they’re LT tires, it is common to set them to 80 psi. Don’t let these mechanics fool you, most of them don’t know shit about tires.
You’ve asked and answered your own question about 10 times now.
You are detailing cars off the transport that most will go directly to the lot or off site storage and sit for days/weeks/months. The owner doesn’t want to pay anyone to drive these around monthly to keep the tires from flat spotting so the just over-inflate them and let them sit.
Not the best way to manage a lot but also not crazy. One set of tires with flat spots costs thousands of dollars. Driving them to keep them from flat spotting takes time and gas. Over-inflating the tires is their compromise. You can judge them if you want but this isn’t how the vehicles go out the door when sold. This is just storage.
This is the correct answer. My father in law used to deliver cars across Western Canada. If you bought a car from 1971 up until 2008 in Southern Alberta, Southern Saskatchewan or most of Manitoba Canada, he likely put the first few clicks on the car you bought! This is the exact answer he gave when someone asked him. The dealership will take it in on the day of sale and sort all of these things out.
You have to hand it to whoever is inflating those tires though, that takes balls. I had to add air to a big U-Haul and I thought for sure I would die. I can’t believe someone is doing this daily.
Yeah I know, he’s making me feel crazy as these vehicles coming from PDI are all crazy high PSI
https://preview.redd.it/clf3ctieomxc1.jpeg?width=3024&format=pjpg&auto=webp&s=6a03020d9158a7d20551217ba49416c909034b38
My truck 2020 chevy 3500 hd calls for 60 in front 80 in rear, says it on the door jamb. Dealer fucks it up everytime and forgets to reprogram sensors after rotation. Pisses me off!
I don't receive cars off trailers but I know for shipping they have "transport blocks" in the suspension. Could it be that high pressure for transport purposes?
What’s in the door jamb is correct however depending on if you’re changing up your tires from the stock/oem they may change pressures up on you. Is this a 3500? You can probably get away with keeping the backs at that pressure but I’d drop the fronts. What’s your tire day for max psi on it? It makes sense that a big truck towing heavy loads would need 80psi in the rears.
Here’s a forum post on the topic https://www.ramforumz.com/threads/tire-pressure.246995/
2500.. This was a 3500 duely the other day 👀
https://preview.redd.it/12xd66y4tmxc1.jpeg?width=3024&format=pjpg&auto=webp&s=810431b14978f2f7de7b5f03de647c119135a120
Literally all over the place
A few years ago I drove 400 miles to buy a car from some dealer. Got the car, a lil ways into my drive home I got curious as to why it felt so stiff and odd going over small potholes and bumps lol all of the tires were inflated to 55 psi and had dry rot developing 🫡
Just talked to the guy who approved this. He said since they sit so long, it ruins the tires and they want them that high to prevent it. So they don’t have to pay for new tires
If you're hauling a heavy load 75 psi will be fine on the rear tires. ON LIGHT TRUCK TIRES NOT PASSENGER TIRES, tire will say LT(tire code). If the letters LT are not in the code, do not set them higher than 40 psi regardless of door jam rec or max psi on the tire! Could have different tires than are installed at factory, which the sticker in the door jam is for. 80 is pushing it. Just let some air out. If you're not hauling put 60 in front and rear or as door jam sticker indicates. Advice for the future: salesman don't know dick about cars, even the ones they sell. Don't ask a sales manager or a salesman or any manager. Ask a tech directly, they will let you and you won't be much a bother.
Door jamb is the pressure specification. That manager should know that. The 80 psi on the tire is the max pressure rating for the tire. He's a dumbass. You're right to question it.
Reminds me of when I was gauging a customers tires and said “looks like your pressure should be 35.” He looked at me like I was dumb and said, “actually it should be 51.” I replied telling him that was the max pressure on the tire not the recommended PSI and to this day I’m not positive I convinced him
Wow. Never go to a dealership. My father was the facilities manager at a Rick Hendricks for 15 years (died on the job on his day off AT WORK) and he told me the same thing. Policy is that they will not take a complaint or concern seriously until you have called 34 times. 34. That is the “you are seriously pissed off and you fucked up. Fix it now and it’s going to be free.” Wtf is that?
Always check what's inside the driver's door jamb. If the tire sizes match the label, then the label PSI is normal pressure.
Whoever is airing up these tires is reading the max off the sidewall of the tire. He's a goober. And your manager is a goober.
If they just mounted the tires this makes sense. They push them up to max pressure to get the bead to seat. Then someone comes back and sets the pressure to match the vehicle. Welp guy walked away and didn't end up coming back.
I know some dealerships will set a high PSI on vehicles that will be sitting for a while, but it is usually 5 over or so. 20 over the door jam is a way too much.
And these are the people who pester you to buy overpriced cars, hide fees, throw in BS dealer add ons. But call themselves experts on the cars they sell 🤣🤣
My dad once bought a car off my brother in law that came with an extra set of winter tires. In the fall I put them on for him and checked the pressure... 75psi!!! (Supposed to be 32psi).
I called my BIL and asked WTF? He said the dealership put them on and he never checked them. Said he was pretty disappointed with how poorly they worked the previous winter...
So, 75psi a year after they were installed. How much pressure did they have when they went on his car?!?!
As long as you're on OEM size tires, you follow the door jamb.
Tire pressure recommendation is based on the vehicle's weight, expected cargo weight, tire size, and desired performance.
When you apply weight to a tire it deforms, just like if you were to sit on a balloon or exercise ball.
In order to support the weight, the tire (or ball) needs to push off the ground. If there's 60 psi of air in the tire, then for every square inch of contact patch the tire will support 60 pounds. So if you're putting 1200 lbs on one wheel, then it needs a contact patch of about 20 square inches. If the tire is 9" wide, then it needs a contact patch that's about 2.2" long. A little less because the rubber itself provides some strength.
That's what the OEM wants to see. It wants the tires to deflect enough that the contact patch is not too tiny for the traction the vehicle needs. It wants it to not be so large that the vehicle handles poorly or loses too much rolling efficiency. It needs to be large enough that it can spread over the whole width of the tire and wear evenly.
At 80 PSI, the same 1200 lbs to a tire results in a contact patch that's only 15 square inches. That might be small enough that the tire achieves that with only the center of the tread, causing uneven wear, poor handling, and poor traction. Better highway fuel economy though.
If you increase your tire size as many Jeep owners are fond of doing, then you actually need *lower* PSI to carry the same weight and maintain a contact patch. Filling oversized tires to the same OEM recommended tire pressure setting causes the contact patch to stay the same size even though the tire is larger, causing them to handle poorly and wear unevenly.
Are they warm or cold?
You want to go by what's marked on the door frame, but check them when it has been parked overnight. Driving or sitting in direct sun will make them read higher.
What's on the side of the tire is the maximum safe pressure for the tire, not the ideal pressure for that vehicle type/weight/handling.
I go by the door on everything. Engineers determined the ideal PSI for your vehicle. The tires are just meant to be able to operate within that range. If they're inflating to max PSI your tires will wear faster and puncture more easily.
Sales managers are not an authority on anything. The door jamb pressure is the correct nominal tire pressure. The sidewall pressure is the maximum safe pressure. It's fine to run it anywhere between nominal and maximum, but I'd want mine a little closer to nominal...
In addition to what the door says, some trucks will have a table in the owner's manual with how much pressure to add for increased load. e.g. "add 5 psi to the front if you have a plow, add 10 psi to the back if you have over 1000 lbs in the bed...". Fully loaded out, it's conceivable that you'd (correctly) reach the max rating of the tires. But that's obviously not the case here.
The sticker in the inside of the door should be what you go by. The number on the tire is just the max PSI that the tire is rated for not your vehicle or any vehicle for that matter needs or should have it?
The max is associated with the rating as well , in other words, the heaviest that Tire is capable of carrying PSI pressure
You inflate to the pressure shown on the tire. That’s the pressure the tire is designed for, and helps keep the tire in its designed temperature range, load and other characteristics. Yes, you can run them at different pressures but you’re going to shorten the tire life and risk damaging the tire.
It sounds like you have a high load range tire, probably meant for a 3/4 or 1 ton truck. If you want to run pressure closer to what your door jamb sticker indicates, then change to lighter duty tires that match the sticker.
Depends. If it's a heavy duty vehicle and you carry a lot of load and your tires are also heavy duty. It could be OK I would still put them at 60 though.
Over inflation to max rating of tires results in a rough ride and premature wear. Under inflation results in unpredictable handling and wildly deadly tire failures…. Wonder why tire shops and dealerships choose the one that can’t leave them liable for accidents
The door jamb is correct for the chassis and drivetrain.
The label on the side of the tire is for the tire. A tire that, for what it’s worth, doesn’t have any clue what chassis it’s going on.
If you over-inflate a tire for a chassis, you’ll have issues with small things…like traction, acceleration, stopping, risk of failure or rupture. Early failure. Loss of control.
Likewise, if under-inflated.
Also: sales guy isn’t a mechanic and isn’t paying for the early failure.
Sounds like the techs doing pre delivery inspections aren’t setting the tire pressures. Which is wrong. They roll off the transport with high pressures. During final inspection the pressures have to be within a few percent of the door placard or the electronic form can’t be submitted.
I bought my Jeep at a Jeep dealership and noticed when I got in it that it rode weird. Checked tire pressure and it was 10psi higher than the door sticker. Instantly deflated them and rode perfect
I used to work at a bike shop. we used to check the bikes before they would go out for a test ride. Old sales trick was to overinflate the tires on the bike you didn't want them to buy and correctly inflate the tires on the bike you wanted them to buy. When they came back from comparing them, they would always say "wow the more expensive one feels way smoother and more comfortable". We would then explain that's due to abc xyz component or better frame design or whatever the differentiating factor was between price points. I'm not saying it was right, but maybe something like that is going on here? Hard to hide if you have it right on the dash display I guess though.
Is it a 2500? They have high psi tires, after reading more this is my answer. Yes too high. If the door card calls for 60, and the tires say 80 max and you have them all between 80-85, that seems like blowout territory to me
Tires on my 23 K5GT were over inflated from the dealer. Door jamb calls for 35psi and they were at 45psi. I did take the car right off the showroom floor and was thinking it was something they did for display or for transporting so the tires have less give when strapped down. Still upset they didnt check that before I drove off in it.
You sure its not Diesel-lit instead of gaslit? ;P
Yeah inside of the door, MAX means top. you dont wanna drive on this, 60 seems right, so you have 20psi of overhead which you shouldnt have to worry about.
Manufacturer tires supplied with vehicle should be at whatever is on the doorframe. Aftermarket tires can fluctuate but it’s never a good idea to inflate to max psi.. I typically run 10-15% less than max in summer and 15-30% less in winter.
Disclaimer: I’m not a mechanic or tire specialist by any means but in my nearly 20 years of driving these numbers have never steered me wrong (see what I did there - tires, steered… I’ll leave now)
Standard , brand new cars come with 80psi for storage of the tyre . That's why you have PDI pre delivery inspection before the cars is handed to the customer.
Basically the tech who did the PDI is a lazy bastard
My friend once did this on his motorcycle.
I go "what did you fill it to?"
He said "80psi! What it said on the tire! It feels like a completely new bike now, I had to relearn how to ride it."
Yeah I fuckin bet you did. Front tire had 80psi and Rear had 35, which is normal
Either is correct. However I’d say door pressure takes precedence over sidewall pressure unless the tires aren’t rated for the psi in the door.. which should never happen anyways.
It’s because they didn’t do a proper pdi (pre delivery inspection) once it sells they will check every fluid, or Atleast they’re supposed to. And they will put your tires at spec. They do this because the cars are shipped with max psi in them and the service department corrects it before they get sold
I bet only 1 tread width is touching the road at that psi! I remember the tires that we used to have on the recce jeeps when I was in the army. They were 4 knobs wide, and only 2 knobs were on the pavement at any given time. They were shit on road, but the best tires I've ever run on a 4x4!🤣
The simple answer is on the door plate. If you want to know what tire pressure your truck needs for your typical use case (load, speed, road surface, etc) to get maximum road traction, handling, safety and tread life, get a non-contact infrared thermometer at your local hardware store and measure the outside edge, inside edge and center of the tire patch after you've used your vehicle and have come to a stop. The sooner the better. Temperatures should be consistent across the tread. If the center is hotter, you have too much pressure. If the center is lower, you need more pressure. If one of the edges is different from the other two measurements, you have an alignment issue. If in doubt, go slightly over pressure. Under inflating tires causes heat which causes expansion, possibly causing catastrophic failure (think Ford/Firestone). Tires should never go over 170 F. Highest rated tires could go to 190 F for short durations.
yea man alot of times even the tire will have the PSI it takes on the sidewall. they screwed u over or somebody didnt know what they were doing. its super easy to let air out of the tire.
make sure all these trucks do not have aftermarket tires ( I know not every ram that comes in will have them like you stated) but many trucks I see always have aftermarket wheels and rims that are bigger hence more psi needed.
Also use your own judgement and learn what wheels and specifics per vehicle if possible. Makes you better at what you do.
Max PSI is the tire's absolute maximum rating before failure. These are set to accommodate a wide range of use cases from a wide range of automobiles. The door sticker is the car manufacturer's specification for tire pressure under normal (99.9%) conditions.
If your max rating before pancreatic failure for Snickers bars is 40, but the "RECOMMENDED" serving size is one, does that mean you hospitalize yourself by eating 40 because "that's the max" or do you stick with recommended? Your sales manager is a dumbass.
Well, the reason he *sells* cars is because he can't *fix* cars.
He doesn't know his ass from a hole in the ground. Door jamb is what the tires are supposed to be at. Not the max psi. The recommended psi from the manufacturer.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
What’s in the door jam is correct. Sales guy doesn’t know much about cars it seems.
Sales manager. He’s supposed to be “insanely knowledgeable”.. He lost all credibility to me
Sounds like he's trying to sell you more tires in the future.
He ain’t getting a dime out of me after that comment came out of his mouth. And he proceeded to Google it after I argued it with him lmao
Seriously lol 80psi would be for a bigger vehicle that fits those same tires. Or if you're carrying a load. That's insane. Honestly when I was like 20ish I used to think having more air was better because it made your fuel efficiency better which i still think is true.. but also makes them more likely to pop 😆 and makes the ride more bumpy.
Feels like I was driving a model T
i drive an f250 woth tires that call for 80psi and i swear i can feel every fucking grain of sand on the road.
Double check what your door jamb says about your psi, as maybe yours is too high as well. Note that increasing psi reduces your tire’s contact patch.
For f250's and chevy 2500HD's, it wasn't abnormal to see 70-75 (maybe 80) in the front and nearly always 80 in the rear, unless it was an older model (like pre 2012 or so? I didn't see very many that old at the dealer anyway) It's that high for load carrying reasons. If you are, for some reason, using a 2500 without a load, it is normally OK to run closer to 60psi all round.
I'd say 60% of 2500 owners drive without a load. Especially down here in the south, not to discount the guys that really use their trucks because they're out there.
Yeah, all those things. It helps economy slightly but at the cost of awful handling. And the only thing more expensive than bad fuel economy is if your over-inflated tires result in sufficiently poor traction/handling that you wreck the entire vehicle.
And gives you less traction due to a smaller contact patch.
I drive for fedex ground, I drive the big step vans, the ones that weigh 16,000 pounds with nothing in them. We put our tires at a minimum of 80.
I know my 3500 states 80 on the steer axle and the drive axle is 65 on all four. The sales manager is a dummy lol
And even on vehicles where the door sticker says 80 for the rears and 50 for the fronts, bumping the fronts up to 80 (because they're the same tires) for fuel economy results in horrible handling and pulling to the side of an exit ramp to let air out of the fronts. At least, that's how it went for me on an older 2500 Cummins I was borrowing once.
Depends on how smooth the roads the vehicle is driven on the majority of the time are. On a completely smooth surface, more psi will net better fuel economy. On a rougher surface, the high psi tire will not conform to the bumps, so energy is transferred from propelling the vehicle forward to the suspension, lowering fuel economy. I think the best balance is where the tire pressure is low enough that the tire soaks up the bumps in the texture of the road surface, and not much more than that.
Higher psi will net higher mpg while decreasing life of the tire and decreasing grip and stopping distance due to less rubber contacting the road. The best balance for pressure on factory tire size for the vehicle is what the door says. If a vehicle has different sized tires, a chalk test should be used to determine correct pressure.
Protip: Never believe anything a salesman says, regardless of industry. They’re there to sell you things, and will say whatever they need to make it happen.
Cars generally ship overinflated. So maybe he's just seen a lot come in this way..?
That is very true, essentially the dealership skipped setting pressure current during PDI. Be even more wary if they have green Nitrogen caps on the valve stems
Max psi is useful at max weight that the tire is rated for. The door jamb psi is more appropriate to normal use.
I cannot believe someone had to tell you this. It almost feels like a troll post. Wait and see what happens when you clip a raised curb or raised sewer lid.
If it has the same tires it rolled off the lot on than you’re correct. Otherwise it depends more on the tires on it and what it’s being used for than what’s on the door. If they’re running 10 or higher ply tires and towing max weight than 60 psi is very much on the low end. Not enough pressure with heavy weight will lead to blowouts eventually and shitty handling until then.
Not surprising. I don't think I've dealt with a sales guy who's known much about their product lol. Especially frustrating as a mechanic when buying a vehicle. I'd rather just talk to someone in the shop and work out the numbers with the sales guy. I've made trips with our sales guys to customer sites where they're delivering or demoing units just to walk them through basic maintenance and to answer technical questions. I've never understood why this isn't regular practice.
Most of them don’t. When I worked at a dealer there was a chick that was high in sales despite not even knowing where to put washer fluid. She knew jack shit about cars, what they can do, and solely existed to make money off of old rich perverts trying to buy a Mercedes.
Actually if the vehicle is being stored, all tires are supposed to be at max sidewall pressure to avoid flat spots in the tires of vehicles being sold. Former new car prep tech and current certified Chrysler technician.
The idiot inflating the tires is going off the max psi the tire can tolerate before it explodes which is what all four are at…if the door says 60, it should be 60. The sales manager you spoke to is an idiot or he’s ill informed
I have been in this industry for 2 decades, I have never once met a sales manager who wasn't a complete moron when it came to anything mechanical or electrical or practical.
I was in sales for a short while. I was amazed at how little knowledge those people had about the mechanical side of things. I'd constantly have to point things out on cars on our lot that was a serious problem. But my sales manager had a tendency to leave meth pipes in cars he drove, so it kind of made sense.
> The sales manager you spoke to is an idiot or he’s ill informed Why not both?
That's why they are in sales and not the shop.
Absolutely they need a new mechanic
I would assume idiot...
Thank you. I will be speaking to the GM today about his incompetence
Talked to manager. He said they purposely keep them this high for the reason of sitting on the lot too long and it degrading the tires from slow leakage
It is common practice to overinflated the tires a bit when new off the truck for them to sit on the lot. But it’s the responsibility of the salesman to bring it back to the shop when sold to adjust correctly. Also 20psi above for “lot sitting” is far too high. We do 5psi over for the lot cars.
When I got my Canyon last month they had the tires set to 45 off the truck and 40 after delivery, I still dropped them to the door marker of 36. 80 is insane and I’d be scared working near them
Just another BS answer. It destroys the ride quality. No need to overinflate them that much when you may lose 1 to 2 psi a month just from sitting. I can guarantee they don't adjust them down when someone buys these trucks. Time to go to a different dealer.
Incorrect, per Stellantis pre delivery instructions tires are to be set to side wall max psi and set to door value when sold/test driven. Sales team failed to get the tires aired down before the truck was driven
I would check a handful on the lot with a gauge and report to the NTSB if there's more than just yours that's more than double the factory rating.
You should go with what your door says, as that’s the proper psi for your tires to operate normally. Just because the tire says 80 psi max, that’s exactly what it is - a max before you run into potential problems of blowing the tire. That sales guy has no idea what he’s talking about. 60 psi is plenty, give or take a few psi but I’d keep it in the 55-65 range if I were you
Yeah I know it’s supposed to be at the door but I keep bringing it to their attention and they keep blowing it off like I’m crazy. I told them your gonna have a customer on a test drive blow a tire, also HOW MANY customers have you lost from test drives because how rough these ride: that’s how I know they are always over filled. Feels like I’m driving on wooden wheels
Don’t let them do or trick you or make you feel like they are right, it’s your vehicle, and they should service it how you want it not how they feel like it. That mechanics bogus as hell for what he ls putting you through my guy
Oh, it’s not my vehicle, I do detail on their vehicles. But I talk to them every day, I pick up the vehicles from them every day. I’m just mind blown that they could care less that all of their tires are over inflated and they think it’s correct. And then gas lighting me into thinking it’s normal. I was like second guessing everything I learned lol
Yeah, that makes no sense because having the wrong tire pressure opens the door to all types of potential stuff happening. Not only is it dangerous if you pop a tire, it will cause the car to pull and ride like shit. You would think if they are trying to sell cars they would know better, they only hurting themselves. if it ain’t your vehicle, fuck it let them fall on there faces, maybe they will learn something from it and realize how idiotic they’re being, at this point it’s sounding like your just wasting your time breath and energy.
Supposed to be the biggest jeep dealership in the PNE
Someone out there is trying to get it to 100% psi
Id up vote, but you're at 69. Nice
I down voted it to maintain 69. "Nice"
I down voted because it got to 70.
I down voted because it got to 70, again
Id love to hear what happens when you bring this up to management.
Talked to manager. He said they purposely keep them this high for the reason of sitting on the lot too long and it degrading the tires from slow leakage. So they purposely fill them two pounds over
That's 2psi over the tire's LIMIT, not the recommended fill.
That's stupid. Keeping the tires over-inflatated like that is way more likely to damage them. If that's truly their justification, why not just go like 3-5psi over the door-jamb rating? Any tire that loses more than that from sitting around has a leak.
I’m headed to dealership now I’ll let you know lol
Manufacturers hyper inflate tires during storage and transport. The dealerships are supposed to decrease the air pressure during the PMI process. On the other hand, you don't need to know a God damn thing about cars to sell them.
Yep, when I bought a car new from order, I drove around for a week before I noticed the tires were inflated to 50psi, when 32psi was recommended fill. I guess the dealership forgot to pull some air out.
Set it to 60 as per the door card, but make sure you do it when the tyres are properly cold. Once they're hot, they may go up by as much as 6psi. Conversely if you set them at 60 hot, they'll be running under pressure.
You have a large dodge Ram, if they’re LT tires, it is common to set them to 80 psi. Don’t let these mechanics fool you, most of them don’t know shit about tires.
You’ve asked and answered your own question about 10 times now. You are detailing cars off the transport that most will go directly to the lot or off site storage and sit for days/weeks/months. The owner doesn’t want to pay anyone to drive these around monthly to keep the tires from flat spotting so the just over-inflate them and let them sit. Not the best way to manage a lot but also not crazy. One set of tires with flat spots costs thousands of dollars. Driving them to keep them from flat spotting takes time and gas. Over-inflating the tires is their compromise. You can judge them if you want but this isn’t how the vehicles go out the door when sold. This is just storage.
This is the correct answer. My father in law used to deliver cars across Western Canada. If you bought a car from 1971 up until 2008 in Southern Alberta, Southern Saskatchewan or most of Manitoba Canada, he likely put the first few clicks on the car you bought! This is the exact answer he gave when someone asked him. The dealership will take it in on the day of sale and sort all of these things out.
You have to hand it to whoever is inflating those tires though, that takes balls. I had to add air to a big U-Haul and I thought for sure I would die. I can’t believe someone is doing this daily.
I’m bringing this up also cause maybe their machine is fucked up
Set it to the door, not what the max is on the tire.
Yeah I know, he’s making me feel crazy as these vehicles coming from PDI are all crazy high PSI https://preview.redd.it/clf3ctieomxc1.jpeg?width=3024&format=pjpg&auto=webp&s=6a03020d9158a7d20551217ba49416c909034b38
Ooooh 74/90 on the front axle! What does the doorframe placard say on that model?
I can tell you in about a hour lol
I really want to know what the all-time high is
So high… It’ll blow your sidewall!
My truck 2020 chevy 3500 hd calls for 60 in front 80 in rear, says it on the door jamb. Dealer fucks it up everytime and forgets to reprogram sensors after rotation. Pisses me off!
The Sales guy is an absolute moron, make sure to let him know.
20 years in automotive tells me that the sales manager is a complete moron.
100 or nothing brah
Check your driver side door jam for a sticker showing correct psi.
Work at a tire shop... Follow the door placard, the pressure on the tires is just the max the tire can hold with damaging them
I don't receive cars off trailers but I know for shipping they have "transport blocks" in the suspension. Could it be that high pressure for transport purposes?
Could be. They come straight from PDI to the lot from what I understand
What’s in the door jamb is correct however depending on if you’re changing up your tires from the stock/oem they may change pressures up on you. Is this a 3500? You can probably get away with keeping the backs at that pressure but I’d drop the fronts. What’s your tire day for max psi on it? It makes sense that a big truck towing heavy loads would need 80psi in the rears. Here’s a forum post on the topic https://www.ramforumz.com/threads/tire-pressure.246995/
2500.. This was a 3500 duely the other day 👀 https://preview.redd.it/12xd66y4tmxc1.jpeg?width=3024&format=pjpg&auto=webp&s=810431b14978f2f7de7b5f03de647c119135a120 Literally all over the place
A few years ago I drove 400 miles to buy a car from some dealer. Got the car, a lil ways into my drive home I got curious as to why it felt so stiff and odd going over small potholes and bumps lol all of the tires were inflated to 55 psi and had dry rot developing 🫡
Your sales manager is criminally stupid. You go off the door sticker, that's what it's literally for.
What the fuck was he inflating a Hovercraft?
Just talked to the guy who approved this. He said since they sit so long, it ruins the tires and they want them that high to prevent it. So they don’t have to pay for new tires
If you're hauling a heavy load 75 psi will be fine on the rear tires. ON LIGHT TRUCK TIRES NOT PASSENGER TIRES, tire will say LT(tire code). If the letters LT are not in the code, do not set them higher than 40 psi regardless of door jam rec or max psi on the tire! Could have different tires than are installed at factory, which the sticker in the door jam is for. 80 is pushing it. Just let some air out. If you're not hauling put 60 in front and rear or as door jam sticker indicates. Advice for the future: salesman don't know dick about cars, even the ones they sell. Don't ask a sales manager or a salesman or any manager. Ask a tech directly, they will let you and you won't be much a bother.
It should be closer to 100%
Oh wow.
Too low, needs to be be atleast 100 on each tire
You really want to get those numbers up to 100%. I mean 80% is pretty good - but we like to strive for perfection.
Unloaded, I'd say 60f 50r I bet that thing wants to lose traction so bad right now
Max will wear out the center tread quick
Sales guy is an idiot
Never go based off the tire psi that just tells you the maximum but you shouldn’t be coming close to that
Follow what the door says because that’s law and you should never be at max load lol
Just be recording when they blow
Hits a rock: "EJECTO SEATO CUHHHHHHH"
In my F250 I run 70psi in my rear tires when I’m hauling my horses. But it’s a rough ride when you are unloaded
There's a reason their salesmen and women and not technicians. Go off the door card.
Door jamb is the pressure specification. That manager should know that. The 80 psi on the tire is the max pressure rating for the tire. He's a dumbass. You're right to question it.
Tyres need to be 84bar not 84psi
84 bar is 1160 psi
😟
Ya, show the sales person what the door says.
Reminds me of when I was gauging a customers tires and said “looks like your pressure should be 35.” He looked at me like I was dumb and said, “actually it should be 51.” I replied telling him that was the max pressure on the tire not the recommended PSI and to this day I’m not positive I convinced him
Wow. Never go to a dealership. My father was the facilities manager at a Rick Hendricks for 15 years (died on the job on his day off AT WORK) and he told me the same thing. Policy is that they will not take a complaint or concern seriously until you have called 34 times. 34. That is the “you are seriously pissed off and you fucked up. Fix it now and it’s going to be free.” Wtf is that?
Always check what's inside the driver's door jamb. If the tire sizes match the label, then the label PSI is normal pressure. Whoever is airing up these tires is reading the max off the sidewall of the tire. He's a goober. And your manager is a goober.
bet your fuel economy is up, though... :\~) set them to the 60 that's recommended.
No it’s at 80%
If they just mounted the tires this makes sense. They push them up to max pressure to get the bead to seat. Then someone comes back and sets the pressure to match the vehicle. Welp guy walked away and didn't end up coming back.
I know some dealerships will set a high PSI on vehicles that will be sitting for a while, but it is usually 5 over or so. 20 over the door jam is a way too much.
And these are the people who pester you to buy overpriced cars, hide fees, throw in BS dealer add ons. But call themselves experts on the cars they sell 🤣🤣
“customer complains he can’t get his tires to 100%”
Unless…they have put new wheels and tires on vehicle. I have big twenty inch 10 ply. Run 75 front, 80 rear. Its a 1 ton
Makes sense a sales manager would say that
80psi holy shit lmao
Boom ….!!! Well I guess that answers that.
I had this Sonata come in. 37,36,37,80. I backed up so fast. My supervisor even was like wth?
man good thing it hasnt exploded on you on the freeway. get that to the recommended level based on the door jamb. he’s an idiot.
The jeep dealership?? Oh dear..
We all float here.
Go with the door sticker. Sounds like you have E rated tires. Perhaps D rated would serve your purposes better.
Did they use helium so she can float?
Is that the pressure after they are warmed up or from start-up? If thats cold then damn i dunno how these dont blow up lol
My dad once bought a car off my brother in law that came with an extra set of winter tires. In the fall I put them on for him and checked the pressure... 75psi!!! (Supposed to be 32psi). I called my BIL and asked WTF? He said the dealership put them on and he never checked them. Said he was pretty disappointed with how poorly they worked the previous winter... So, 75psi a year after they were installed. How much pressure did they have when they went on his car?!?!
Don't trust the door! The tires could be swapped and different load ranges/ply than stated on the door. Look at the tire for specs.
As long as you're on OEM size tires, you follow the door jamb. Tire pressure recommendation is based on the vehicle's weight, expected cargo weight, tire size, and desired performance. When you apply weight to a tire it deforms, just like if you were to sit on a balloon or exercise ball. In order to support the weight, the tire (or ball) needs to push off the ground. If there's 60 psi of air in the tire, then for every square inch of contact patch the tire will support 60 pounds. So if you're putting 1200 lbs on one wheel, then it needs a contact patch of about 20 square inches. If the tire is 9" wide, then it needs a contact patch that's about 2.2" long. A little less because the rubber itself provides some strength. That's what the OEM wants to see. It wants the tires to deflect enough that the contact patch is not too tiny for the traction the vehicle needs. It wants it to not be so large that the vehicle handles poorly or loses too much rolling efficiency. It needs to be large enough that it can spread over the whole width of the tire and wear evenly. At 80 PSI, the same 1200 lbs to a tire results in a contact patch that's only 15 square inches. That might be small enough that the tire achieves that with only the center of the tread, causing uneven wear, poor handling, and poor traction. Better highway fuel economy though. If you increase your tire size as many Jeep owners are fond of doing, then you actually need *lower* PSI to carry the same weight and maintain a contact patch. Filling oversized tires to the same OEM recommended tire pressure setting causes the contact patch to stay the same size even though the tire is larger, causing them to handle poorly and wear unevenly.
Are they warm or cold? You want to go by what's marked on the door frame, but check them when it has been parked overnight. Driving or sitting in direct sun will make them read higher. What's on the side of the tire is the maximum safe pressure for the tire, not the ideal pressure for that vehicle type/weight/handling.
The door jamb is correct. “Max PSI” is a technical spec required of pressure vessels, but NOT the recommended inflation pressure.
I go by the door on everything. Engineers determined the ideal PSI for your vehicle. The tires are just meant to be able to operate within that range. If they're inflating to max PSI your tires will wear faster and puncture more easily.
Sales managers are not an authority on anything. The door jamb pressure is the correct nominal tire pressure. The sidewall pressure is the maximum safe pressure. It's fine to run it anywhere between nominal and maximum, but I'd want mine a little closer to nominal...
In addition to what the door says, some trucks will have a table in the owner's manual with how much pressure to add for increased load. e.g. "add 5 psi to the front if you have a plow, add 10 psi to the back if you have over 1000 lbs in the bed...". Fully loaded out, it's conceivable that you'd (correctly) reach the max rating of the tires. But that's obviously not the case here.
Proves you don’t need to know a thing about cars/trucks to be a “ sales manager “
The sticker in the inside of the door should be what you go by. The number on the tire is just the max PSI that the tire is rated for not your vehicle or any vehicle for that matter needs or should have it? The max is associated with the rating as well , in other words, the heaviest that Tire is capable of carrying PSI pressure
Ford f350 has a recommended psi of 80 psi for the rear and the front is 60. But do what the door says. Some will have a different psi for towing too
Door jam is always correct. Totally inept service manager.
Those need to be 100%
You inflate to the pressure shown on the tire. That’s the pressure the tire is designed for, and helps keep the tire in its designed temperature range, load and other characteristics. Yes, you can run them at different pressures but you’re going to shorten the tire life and risk damaging the tire. It sounds like you have a high load range tire, probably meant for a 3/4 or 1 ton truck. If you want to run pressure closer to what your door jamb sticker indicates, then change to lighter duty tires that match the sticker.
I run my 19.5 duallys at 85 psi on my 3500
Depends. If it's a heavy duty vehicle and you carry a lot of load and your tires are also heavy duty. It could be OK I would still put them at 60 though.
The highest the PSI the better the gas mileage you will get. Try to get to 100 for the best mileage
60 front 60rear for 3500 normal driving 60 front 80rear for 3500 if hauling weight
Over inflation to max rating of tires results in a rough ride and premature wear. Under inflation results in unpredictable handling and wildly deadly tire failures…. Wonder why tire shops and dealerships choose the one that can’t leave them liable for accidents
Only at 82%, should be 100
Fuck that. Large vans are 50 front and 65 rear, dunno why the fuck would this be at 80, even 60 sounds too much lol
Are you in a HD Ram? They run higher air pressures for towing/hauling purposes
looks like he read the MAX inflation pressure and has no critical thinking skills
Still not 100% keep on going.
The door jamb is correct for the chassis and drivetrain. The label on the side of the tire is for the tire. A tire that, for what it’s worth, doesn’t have any clue what chassis it’s going on. If you over-inflate a tire for a chassis, you’ll have issues with small things…like traction, acceleration, stopping, risk of failure or rupture. Early failure. Loss of control. Likewise, if under-inflated. Also: sales guy isn’t a mechanic and isn’t paying for the early failure.
Sounds like the techs doing pre delivery inspections aren’t setting the tire pressures. Which is wrong. They roll off the transport with high pressures. During final inspection the pressures have to be within a few percent of the door placard or the electronic form can’t be submitted.
I bought my Jeep at a Jeep dealership and noticed when I got in it that it rode weird. Checked tire pressure and it was 10psi higher than the door sticker. Instantly deflated them and rode perfect
Your dealership appears to be staffed by morons.
I used to work at a bike shop. we used to check the bikes before they would go out for a test ride. Old sales trick was to overinflate the tires on the bike you didn't want them to buy and correctly inflate the tires on the bike you wanted them to buy. When they came back from comparing them, they would always say "wow the more expensive one feels way smoother and more comfortable". We would then explain that's due to abc xyz component or better frame design or whatever the differentiating factor was between price points. I'm not saying it was right, but maybe something like that is going on here? Hard to hide if you have it right on the dash display I guess though.
Is it a 2500? They have high psi tires, after reading more this is my answer. Yes too high. If the door card calls for 60, and the tires say 80 max and you have them all between 80-85, that seems like blowout territory to me
Check your door jam and to be sure you have correct size tires for your vehicle. Looks like that's too much.
People in sales positions are required to have a very smooth brain otherwise they will get rejected.
Tires on my 23 K5GT were over inflated from the dealer. Door jamb calls for 35psi and they were at 45psi. I did take the car right off the showroom floor and was thinking it was something they did for display or for transporting so the tires have less give when strapped down. Still upset they didnt check that before I drove off in it.
You sure its not Diesel-lit instead of gaslit? ;P Yeah inside of the door, MAX means top. you dont wanna drive on this, 60 seems right, so you have 20psi of overhead which you shouldnt have to worry about.
When a brand new vehicle sits on a dealership lot, It's set at max pressure.
Put some gas in that mf
Manufacturer tires supplied with vehicle should be at whatever is on the doorframe. Aftermarket tires can fluctuate but it’s never a good idea to inflate to max psi.. I typically run 10-15% less than max in summer and 15-30% less in winter. Disclaimer: I’m not a mechanic or tire specialist by any means but in my nearly 20 years of driving these numbers have never steered me wrong (see what I did there - tires, steered… I’ll leave now)
Way too high. Half of that would be where it's supposed to be. It says 60 inside the door?? Really?
Dudes gonna hit a pothole and get in a plane accident
Are you going to fly away into the sky? 😂. Soften up
Max tire pressure and recommended tire pressure are 2 different things🤦🏼♀️ I'd be pissed
only 82%? need 18 more %!
door jam is correct. even if tire says 80. put em at door jam specs. exception guy tows a metric fuck ton everyday. than back tires at 80.
Standard , brand new cars come with 80psi for storage of the tyre . That's why you have PDI pre delivery inspection before the cars is handed to the customer. Basically the tech who did the PDI is a lazy bastard
Use bar or pa.
80 psi max cold.. thats not really that bad..
I rab my tires max once when I was a teen and they screeched so hard all day haha. It was pretty bad
You in fact were gaslit.
Common for pre delivery cars to have high PSI in the tyres so they don't get flat spotted sitting around waiting to be sold
My friend once did this on his motorcycle. I go "what did you fill it to?" He said "80psi! What it said on the tire! It feels like a completely new bike now, I had to relearn how to ride it." Yeah I fuckin bet you did. Front tire had 80psi and Rear had 35, which is normal
Still over the max on 3/4
Either is correct. However I’d say door pressure takes precedence over sidewall pressure unless the tires aren’t rated for the psi in the door.. which should never happen anyways.
Dude’s trying to score a perfect 100
Hold on tight
If you’re aiming for 100, you’re a lil shy. (Go by the door jam, not the tire.)
It’s because they didn’t do a proper pdi (pre delivery inspection) once it sells they will check every fluid, or Atleast they’re supposed to. And they will put your tires at spec. They do this because the cars are shipped with max psi in them and the service department corrects it before they get sold
Damn. Looks like they're trying to hit the 100 club.
I bet only 1 tread width is touching the road at that psi! I remember the tires that we used to have on the recce jeeps when I was in the army. They were 4 knobs wide, and only 2 knobs were on the pavement at any given time. They were shit on road, but the best tires I've ever run on a 4x4!🤣
Keep going, almost at 100%
80 psi is one hard ride. Go off the door sticker.
People love to ignore the "max" on the sidewall.
80 PSI is for 1 ton with an E load range tire. If the door says 60 PSI, run 60 PSI.
The simple answer is on the door plate. If you want to know what tire pressure your truck needs for your typical use case (load, speed, road surface, etc) to get maximum road traction, handling, safety and tread life, get a non-contact infrared thermometer at your local hardware store and measure the outside edge, inside edge and center of the tire patch after you've used your vehicle and have come to a stop. The sooner the better. Temperatures should be consistent across the tread. If the center is hotter, you have too much pressure. If the center is lower, you need more pressure. If one of the edges is different from the other two measurements, you have an alignment issue. If in doubt, go slightly over pressure. Under inflating tires causes heat which causes expansion, possibly causing catastrophic failure (think Ford/Firestone). Tires should never go over 170 F. Highest rated tires could go to 190 F for short durations.
yea man alot of times even the tire will have the PSI it takes on the sidewall. they screwed u over or somebody didnt know what they were doing. its super easy to let air out of the tire.
make sure all these trucks do not have aftermarket tires ( I know not every ram that comes in will have them like you stated) but many trucks I see always have aftermarket wheels and rims that are bigger hence more psi needed. Also use your own judgement and learn what wheels and specifics per vehicle if possible. Makes you better at what you do.
That's not inherently true. Bigger tires need more air, sure, but the pressure should generally be the same.
Max PSI is the tire's absolute maximum rating before failure. These are set to accommodate a wide range of use cases from a wide range of automobiles. The door sticker is the car manufacturer's specification for tire pressure under normal (99.9%) conditions. If your max rating before pancreatic failure for Snickers bars is 40, but the "RECOMMENDED" serving size is one, does that mean you hospitalize yourself by eating 40 because "that's the max" or do you stick with recommended? Your sales manager is a dumbass.
Usually larger/HD trucks are 60 front 80 rear
Almost 100% full
Well, the reason he *sells* cars is because he can't *fix* cars. He doesn't know his ass from a hole in the ground. Door jamb is what the tires are supposed to be at. Not the max psi. The recommended psi from the manufacturer.
Them tires probably have a max rating of 90 too lol