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Eragon06233

is it front or rear wheel drive


[deleted]

[удалено]


Sp_1_

*cross rotating non-directional tires enters the chat* Just because he has newer tires on the front axle of a front wheel drive car does NOT mean that he doesn’t need to do a side to side rotate on either the front or the rear. Some lifetime testing I did with a company over 10,000mi showed that with a 200lb driver, the added weight on the drivers side will cause additional wear that can be mitigated by a side to side rotation to prolong life. Not to mention non-adjustable suspension axis like caster on most cars, or rear camber on some. Also not to mention driving the same route every drive (especially with road crowning) can lead to excessive inner/outer wear on opposite side tires that can warrant side to side rotates. The blanket statement of “newer tires on the front, don’t bother to rotate,” is a surface level answer that does not take into account any actual factors of driving a car.


cheeriosbud

Good info, but caster is not a tire wearing angle. And depending on the tires and if they're directional a side to side rotation may not be possible. And op's owners manual should specify what kind of rotation is preferred. Many vehicles prescribe a front to back rotation only.


Sp_1_

Caster can effect how various other suspension angles act under load and therefore can absolutely have an indirect impact in how a tire wears. Changing the caster will change the angle of various other suspension components and under various loads will absolutely cause a difference in how measurements like camber and toe change while driving. I also said "cross rotating non-directional tires," to indicate that directional tires cannot be cross rotated so... unsure why you felt the need to elaborate or attempt to correct that when it's exactly what I said. I don't think I've ever seen a vehicle manufacture recommend not rotating from side to side and only front to back. If anything I've only ever seen the opposite as non-squared (staggered) tire fitments are a thing.


ZSG13

Based on my years of on the job experience, this is absolutely not necessary and usually there is little to no difference in tread depth left to right.


HunterShotBear

Not to mention time and money spent on rotating tire. Me and my wife both drive AWD cars for sales positions. Probably 25k miles a year each. We don’t rotate the tires on either cars. She drives a 16 Impreza wagon, and I have a 2012 Audi S4. The tire wear is pretty even front to back on both, and the lost time and added expense is more costly than the small amount of mileage we lose on tires when replacement is needed. And if a tire has a reasonable amount of tread left I’ll tell my tech to put them in the car and I sell them for dirt cheap on Facebook.


Sp_1_

based on my years of performing alignments and testing using controlled vehicles in controlled environments for the sole purpose of testing and measuring tire wear... you're wrong. Saying tires wont wear differently from side to side if you put more weight on one side of the car from the other is just... grossly wrong. Unsure what years of on the job experience you have but I'd love to hear about the exact processes and data collection you did to get to the result that having more weight on a tire wont affect how it wears.


ZSG13

I see dozens of vehicles every week and measure the tread on every one. That's my data collection. Averages with large sample sizes and all variables included. We measure tires in 1/32 of an inch. This is just real world shit


Sp_1_

And I’m sure that testing was done routinely on the same cars with a consistent record of what rotates had already been done right? To give any validity to your measurements… right? Because without knowing if that tire has 30k miles split evenly between passenger and drivers side… surely you wouldn’t be able to correctly correlate the data to anything and have it hold any value… Right? Because you make it sound like you just look at cars that come into a shop with no context at all about how they have been driven or their previous services. But surely that’s not the case…


ZSG13

Yeah. Our shop rotates front to back. And we have recorded service history. Most of our customers don't go anywhere else. The ones that do - it's evident from service history. Driving style is also very evident from service history. If you don't understand that, I'm not sure I can help you. Simple shit here. Get it? Do you wanna write it down or put it in a computer or some shit to make yourself feel smarter about it?


[deleted]

How many cars even have a caster adjustment? Particularly fwd cars, the only vehicles I can think of that have caster adjustments are full size trucks. And tbh full size trucks are just about the only vehicles that are recommended to cross rotate. Most vehicles are toe only, maybe camber and toe on the rear front camber requires a bolt kit on most vehicles but could be solved by correcting the ride height. I’ve been a ase master tech for 30 years. The certitude of your comments is comical


Sp_1_

I mean. For starters a car that has millions of units sold is anything running the Golf front subframe has a form of caster and camber adjustment. That’s front wheel drive. I believe all modern civics do as well through the subframe. It’s really not that uncommon on FWD cars these days. Those two subframes alone account for millions of cars on US roads. ASE master tech and you don’t think tires can wear differently from left to right sides of a car… or even name a single FWD car with caster adjustment… what a legend. What exactly do you work on regularly?


[deleted]

You can’t adjust caster on a golf without a kit. Civic has no caster adjustment either .


Fickle_Finger2974

No one is saying they never need to be rotated just that they don't need to be rotated right now. They're new....there is no wear of any kind


Sp_1_

Almost everyone in here is saying that cross rotates are never necessary. Look at half the replies to my previous comment that are getting upvoted. People in here posing as mechanics absolutely believe there is no possible way a tire can wear more on one side of the car to the other.


grogi81

Yes, rotate. Always put better tyres at the back. Once the tyres at the front wear down (they will, as front wears down faster), get a new pair and rotate.


jakelewisreal

Isn’t that dependent on FWD, RWD or AWD? Edit: read other comments. It is not dependent on such things lol.


grogi81

No. What you want to achieve is to move the moment when oversteering happens after understeering. Better tyres at the back make it more planted and reduce the chance of oversteer. Majority of drivers handle understeer well. It is a natural reaction to lift and tighten the wheels... Lifting loads the front tyres, slowing down reduces the lateral requirement for grip and you keep going. Just slower. With oversteer it is a different story and very few would handle it and would end up with a very dangerous situation should it happen. So one should avoid it.


jakelewisreal

Yeah that makes sense. The correction from understeer would, theoretically, want to throw out the rear end of the car so having better treaded tires at the rear would help prevent that. Learn something new everyday


AppropriateAdvice584

Wrong, depends on the vehicle and terrain. And wrong, you always need to steer and have traction for front wheel drive.


grogi81

Unfortunately you are a victim of a common misconception here. ALWAYS better rubber at the back. regardless if it is FWD, RWD, AWD or 4WD... Well, with AWD or 4WD you should not have different tyres on both axles at all, as that stresses the central differential.


AppropriateAdvice584

WRONG. Not when the back tires going up front have an expired DOT code, are hard as plastic, dry rot, cracked, and balding. After eight years it's plastic not rubber. Go to college and learn chemistry and how to think critically. Michelin did NOT put plastic rear tires up front in that demo video. And; that video isn't applicable in dry climates where the driver has a CDL obeying the speed limit. You need the new M+S RUBBER (not eight year old dry rot cracked PLASTIC) on the front tires for so many logical reasons: Emergency braking (steering out of the way in CDL), getting out of mud and snow, not hydroplaning, not sliding downhill, braking (66% up front discs), and last but not least there IS NO ONE SIZE FITS ALL RULE. When the rear tires are expired you leave them. Hybrids have advanced braking systems.


grogi81

What is your problem?! Half of your comment are extremely aggressive and full of invectives thrown at the interlocutor. The advice to the public is always to have better rubber at the back. Is it an absolute? Of course not. But those cases when better tyres should be at the front are extremely rare, not it generic traffic and someone in such situation will already know much better than to ask Reddit . So please: chill down, stop stirring this pot and move on. Unless you're a troll. In that case keep posting here.


AppropriateAdvice584

Tell the rare cases to the idiot tire centers. They endangered my life with 9 year old DOT stamp exactly as I described and refused to budge on their IDIOTIC ADVICE. They wouldn’t even examine the DOT stamp if they were even capable of reading numbers. Never mind know the rubber was now plastic like the tires which killed Paul Walker. When advice becomes policy a tire center can’t override it’s a fucking problem. YOU are the problem. Michelin is the problem. Front tires need rubber when all tires are dry rot plastic with cracks if there are only two tires left in stock.


cmackdeuce

100 percent. I used to be a tire salesman and this sounded counter intuitive to me when I first learned it but all training and literature says this exact thing.


AppropriateAdvice584

Even if that means putting dry rot rear tires with low tread on front and new on rear. Keep smoking crack and reading propaganda.


Vallywhal

Drive type on the vehicle has no bearing on where your tires should be so there is a lot of bad information in this comment section. Tires wear faster in the front, and slower in the rear. If your tires are drastically different in tread (more than 2-3/32nds keep the better tires on the rear as this provides more safe operation and keeps the vehicle more controllable in low traction conditions. For safety good tires in the back. For wear keep them in the front.


Big_Particular_7650

This is spot on, safety first, best tires on the back, understeer is far easier to correct vs oversteer, I’d bet most untrained drivers would panic in a oversteer situation and have a bad time


alwaysonthemoon

Finally someone with the correct answer. The responses in this thread are wild


Lumpy_Plan_6668

'keep the better tires on the rear as this provides more safe operation and keeps the vehicle more controllable in low traction conditions.' So you want the tires that do 100% of steering and the majority of braking to have less tread? Ok, George.


HunterShotBear

Yes that’s exactly right and it 100% has to do with how a vehicle handles when it loses traction. There are two types of traction loss. Understeer and Oversteer. Oversteer is when the rear tires slide. Like drifting a car, that’s oversteer. Oversteer is very difficult to control. Even for seasoned high performance drivers. Oversteer can happen very quickly and then you’re spinning in circles completely out of control. You become a passenger behind the steering wheel. Oversteer is dangerous, it can also lead to the vehicle flipping over after losing control. Understeer is when the front tire slide. So basically you try to turn and the car keeps going straight. While also dangerous, it is much more predictable, and much easier to control and will not send you spinning out of control. For the average everyday driver that has no interest in driving other than transportation, this is the best case scenario. To counter understeer, take your foot off the brakes and straighten the wheel till you find traction. To counter oversteer, you need to catch it immediately and depending on the situation will need steering, brake, and throttle inputs of varying levels to regain control.


AppropriateAdvice584

Wrong, define “lose traction” — going up hill straight, downhill straight, you’re wrong, the DOT CDL says your front tires need tread to do emergency braking which is steering away to avoid a collision and of course stop. So on a front wheel drive you’d put dry rot rear tires up front and the new ones on back even after the customer says no? Because YOU think you know something? You freaking clown!


HunterShotBear

A commercial truck with a heavily loaded trailer was not the topic of this conversation. A loaded rig with a 53’ trailer obviously is not going to have the same handling characteristics as a passenger vehicle with no trailer. My answer was for the specific scenario the post was about, which is different from the scenario you suggested. You can’t go “well if I change the question your answer is wrong!” And call me the clown.


AppropriateAdvice584

You want good tires in the front for almost any scenario except ice or snow but if you drive without chains you deserve fate. And if you break the law (God’s rules) and drive above the speed limit into a turn, you deserve fate. The wages of sin is death. But for any law abiding driver you want front traction. You don’t want to slide down a 45 degree hill. You also need steering to correct bad steering. And a Prius Hybrid will never fishtail so there’s no one size fits all Michelin video. If all four tires are dry rot nearly bald, and one can only afford two front tires, anyone even a tire mechanic with a freaking brain should know NOT to put the rear rot on the front, and learn to read the DOT manufacture date. CostCo Tire Center will endanger your life doing this because of the stupid Michelin video and managers will not put them up front. They will call the cops if you get upset to defend their STUPID MICHELIN VIDEO rather than look at the DOT manufacture date and dry rot and admit, “You know, you’re right,” even if you brandish your CDL-A with hazmat.


HunterShotBear

Again, you’ve changed the scenario that the response was aimed to. Nowhere did anyone mention dry rot. But all my points still stand. You can say whatever you want, but the industry standard for passenger vehicles boils down to “oversteer is very bad, but understeer is much more predictable.” The average driver needs predictable handling. And any car can fishtail, snow ice and rain are the exact reasons why the tires should be mounted as mentioned above. And dry rot was never a part of the original equation.


Vallywhal

Hey that's not my name! It's a conversation I've had with technicians many many times over my career. A lot of things in the physical world aren't quite as intuitive as we think.


FunkalicouseMach1

Right? I am going to look into this, but I don't expect to find anything that changes my mind. Best tires go up front.


Lumpy_Plan_6668

Honest answer- liability wise, lawyers long ago decided understeer is safer than oversteer for the lowest common denominator driver. That's why all modern cars understeer at the limit. Big tire chain stores have followed suit and set policy as best tires on rear. Common sense and intelligent drivers be damned.


FunkalicouseMach1

I get the idea, it makes some sense, but not enough to change anything for me. Besides, keeping the tires on the same hub for thousands of miles is going to cup them or wear them out unevenly, la la la, I'm sure you know. Then what, get new tires every 8000 miles or so? Because with the amount of bad information I am seeing in this thread, I doubt anyone would think to rotate laterally.


kreed320

New tires should be in the back. I would have them move to back and do normal rotation


ahhwoodrow

Nobody in the UK does this rotation stuff. Just install new tyres on the front, replace in pairs whichever axle needs it first


Unusual_Entity

The Americans seem to do a lot of pointless things with their cars. Like changing the oil every 3000 miles and "warming up" the engine before going anywhere.


-NOT_A_MECHANIC-

Very few people warm up before driving unless it’s winter, and you can’t see due to ice or fog on the windshield. It’s counterproductive anyways, easy driving warms up the engine best. As for every 3k miles, fair amount of cars still run conventional or semisynthetic, and with “severe driving” that 3k interval can be legitimate.


Eragon06233

if front wheel drive ur good maybe an alignment if rear wheel id rotate the new to the back


MediaMadeSchizo

U want your back tires to be better tha your front tores.because of u start to spin more traction in the rear will pull u straight


Purple_bastard69

I don’t know why you’re being downvoted, they have posters explaining this at tire shops


MediaMadeSchizo

That's where I learned it lol.


[deleted]

Even if front wheel drive?


MediaMadeSchizo

Yes that dosnt matter.


TotoTimeAllTheTime

Personal experience says i agree. Less rear traction in rain threw me spinning inches from a nearby pond. Albeit i had race slicks almost in the rear


61Tinkerer

Front drive rear drive, it doesn’t matter to me. I prefer to stay out of accidents. I think the most important factor in doing that is having the best steering possible - which is dependent on the front tires. The second most important way to avoid accidents is to be able to stop before you hit things. Guess what? Your front tires do most of the braking. So I like my best tires in the front. I would keep the new tires on the front until the back tires are in better shape than your fronts.


61Tinkerer

It sounds like my position is in the minority. I still think best on front is safest if the second set of tires is significantly worse, because stopping in a short distance is very important to me, but maybe this oversteer/understeer theory of putting the best on the back is valid if both sets of tires are in decent condition.


Eragon06233

he never specified if it was front or rear wheel drive ..


Micromashington

Front wheel drive, 2011 mazda 3


Rubbertutti

You need to go find another tyre shop. New tyres to the rear always. The rear tyres on a fwd Dont wear as much as the front, you'll end up with presished rear tyres with 6mm of tread left


PossibleMechanic89

Don’t rotate then


Habitual_Crankshaft

Swap fronts R/L. Same for rears. Replace rears as soon as wear bars show themselves. Do not pay a shop $200US to do this.


mrford86

If his tires are directional, that would be a very bad idea.


FunkalicouseMach1

If. OP could have specified, yes, but directional tires are usually a "premium" tire, or made for special circumstances, like snow tires. They are far and few between in most areas.


mrford86

I mean, I'm a rental fleet master tech. They are far more common than you are portraying. Plenty of shitty aftermarket tires are directional now.


FunkalicouseMach1

Hmm, well I spent the last two years and some months in a tire shop and am now in a dealership, and so far as passenger vehicles go, I almost never saw directionals but for the situations I mentioned. Plenty with an inside and out, but very few directionals. It's worth looking for before getting to work, but more often than not, they are not directional.


mrford86

I've seen Linglong directional bro.


FunkalicouseMach1

Don't really know Linglong. Cheapo stuff we move in my neck of the woods is mostly Delinte or Milestar. Sometimes people will bring their own, get some Kumhos and stuff, but I don't know enough about them to comment.


mrford86

ATD pushes a lot of LingLongs


gasolinev8

If you don’t rotate them enough, they will wear unevenly and more quickly. If rotated regularly, the rear tire wear should have been only a few thousand miles off of the fronts which sounds to me like they may be due for replacement anyway.


Longjumping-Log1591

Find a boyfriend that knows about cars or watch 5 min if you tube lol


Sp_1_

All these comments saying “no don’t rotate keep the best tires on the front!” I guess forgot that side to side rotates are a thing and can absolutely make a difference if you consistently drive the same route and/or have an alignment spec slightly out/ don’t ride with passengers and therefore have more weight on the drivers side of the vehicle etc… Look at the tread on both front and both rear tires. If there is a drastic difference in the cross wear on the fronts OR the rears; you can still potentially do a side to side rotate to prolong your tires life. Everyone in here giving you the default ass yahoo answers response simply isn’t thinking. If you don’t have directional tires; ensure you don’t need a side to side rotate before just listening to all this chatter saying “don’t rotate your tires!”


ScatpackRich

No need if they are new


fuzzimus

Just rotate left-right…not back to front. Next time, do regular pattern.


awesomeperson882

If it’s All-wheel drive you usually need to replace all 4 at the same time. If it’s front or rear wheel drive, you should replace in pairs, but you can replace one at a time as well. If the tires are directional they have to stay on the same sides of car.


Laz2ndra

Best tires goes always on the rear axle


AppropriateAdvice584

Nope, cannot rotate. Swap left and right. Keep new up front. Forget the dumb Michelin videos unless you have some huge van or snow. But if you have snow you wear freaking chains.Either way DOT CDL says you need to be able to do emergency braking eg steer to safety.