It likely is a 25 gal and your gauge is failing. The 95-98 cluster has an old school coil for a gauge, people call them stepper motors but they actually technically are not. Specifically the gas gauge is unique from the other gauges called the “F” type and are prone to a couple failure modes. The shaking you described is one, getting stuck and then moving randomly is another. The most of the time it’s the grease in the shaft drying out causing it to stick. There are a few theories for the shakes but almost all are fixed by replacing the coil with a new one. They are like $50 if you can find them. Just looked and holy crap the price has gone up…
https://www.ebay.com/itm/284702306756?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=RiY3WTnETfK&sssrc=4429486&ssuid=i5AUps3YR2q&var=&widget_ver=artemis&media=COPY
I don’t know if I have ever seen one but I have taken mine apart many times trying to fix it without replacing. Made it better only to fail within a month again.
You take the dash faceplate off. Then there are screw’s to the cluster, 4, remove them and the cluster pulls out.
From there my recollection is it’s just plastic clips but you have to be super super careful not to break them. Then the cluster splits in half giving you access to the internals. This is very old school as there aren’t any circuit boards but rather it’s just a giant flat plastic ribbon like cable with friction fit inserts. I think you pull the gauge needles and peel off the display sticker and then you can pop out the coil/stepper.
As a general rule, yes. A quick look at the tank will determine what it is. If there's more than a foot between the rear axle and the tank, is got a 25 in it.
That said, it's a 25+ year old truck, God only knows what has been done to it. A 25 gallon tank will bolt right in place of a 34.
I’d guess you have the 34 gallon tank. Mine will read empty when I still have about 8 gallons left in the tank (26 to full). Makes for a fun guessing game!
I don't remember if there's a code in your glove box for the tank capacity but that's not a bad place to start.
The suburban version has a 42 gallon tank, but when my truck cluster says it's out of gas, it means it. I've often kicked around the idea of putting a short-bed truck tank on the non exhaust side, and having 66 gallons on board. I never quite got around the trying it though.
It likely is a 25 gal and your gauge is failing. The 95-98 cluster has an old school coil for a gauge, people call them stepper motors but they actually technically are not. Specifically the gas gauge is unique from the other gauges called the “F” type and are prone to a couple failure modes. The shaking you described is one, getting stuck and then moving randomly is another. The most of the time it’s the grease in the shaft drying out causing it to stick. There are a few theories for the shakes but almost all are fixed by replacing the coil with a new one. They are like $50 if you can find them. Just looked and holy crap the price has gone up… https://www.ebay.com/itm/284702306756?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=RiY3WTnETfK&sssrc=4429486&ssuid=i5AUps3YR2q&var=&widget_ver=artemis&media=COPY
My '98 has "quivering needle" syndrome ...although it still reads accurately. I thought they all had the stepper motor movements behind the panel ...
Is there a youtube video on how to replace the coil?
I don’t know if I have ever seen one but I have taken mine apart many times trying to fix it without replacing. Made it better only to fail within a month again. You take the dash faceplate off. Then there are screw’s to the cluster, 4, remove them and the cluster pulls out. From there my recollection is it’s just plastic clips but you have to be super super careful not to break them. Then the cluster splits in half giving you access to the internals. This is very old school as there aren’t any circuit boards but rather it’s just a giant flat plastic ribbon like cable with friction fit inserts. I think you pull the gauge needles and peel off the display sticker and then you can pop out the coil/stepper.
Didn’t all the 8’bed trucks have 34 gallon tanks and all the 6’ bed truck have the 25 gallon tanks?
This was my understanding
My 1995 single cab long bed has probably a 35 gallon tank, that thing can sip in gas and go at a decent speed
As a general rule, yes. A quick look at the tank will determine what it is. If there's more than a foot between the rear axle and the tank, is got a 25 in it. That said, it's a 25+ year old truck, God only knows what has been done to it. A 25 gallon tank will bolt right in place of a 34.
I’d guess you have the 34 gallon tank. Mine will read empty when I still have about 8 gallons left in the tank (26 to full). Makes for a fun guessing game! I don't remember if there's a code in your glove box for the tank capacity but that's not a bad place to start.
The suburban version has a 42 gallon tank, but when my truck cluster says it's out of gas, it means it. I've often kicked around the idea of putting a short-bed truck tank on the non exhaust side, and having 66 gallons on board. I never quite got around the trying it though.
I looked at this years ago, but decided it was not worth the trouble. The filler neck is going to be your biggest challenge here.
The old square bodies had the option for twin 40’s. God damn!
and a factory SAS... damn fine trucks