Tire pressure

[btoscano]

I have BFG A/T KO 235/85 R16 E rated tires. When new I set them to 55 front and 50 rear.



The front tires are wearing slowly and had 51-52 psi. The rear tires were wearing fast and turns out they were actually 35 and 45!! I'll have to keep an eye on that one tire. Maybe the lower psi was causing the wear? Or does the drive axle on these trucks just wear fast?





Thanks,

Brian

 

[KSommer]

rear pressure shouldn't cause alot of tire wear. especialy if the truck is empty. my first guess is the rear axle is bent, and the rear tires are fighting each other. or they could be bad tires, you didn't buy blems, did ya?

kent

 

[JLEONARD]

rear tires were wearing fast

My nephew has this problem too... but his is a case of trying to accelerate faster that the tires can bite. :-laf

He does not deny this thoery.



You don't have a bent rim do ya??

 

[bgilbert]

Air them up to the cold psi spec on the side of the tire ~ probly 80psi, no more abnormal wear. . except your spine :-laf. .

 

[btoscano]

When I put 80 psi in rears of my 1990 D250 CTD, the center wore down faster than the edges, as if they were overinflated.



Most of the miles on the truck are 75-78 MPH on the freeway, up and down hilly interstates.



The installer used a Hunter GSP9700 machine. He tested the rims on a few tires because they came back with a higher score than he liked. He turned 2-3 of the tires on the rims to lower or try to lower the score. As I recall he said the rims (not steelies) were OK.



-brian

 

[bgilbert]

Brian, maybe the rear tires on your 90 had D rated tires= 50psi. Read what it says on the sidewall of the tire. Air them up as close to that spec COLD for best wear/life out of them.

 

[btoscano]

Bill,



They were E-rated, 80 psi.



I bought Bridgestone Dueler A/T Revo 235/85 R16 E-rated for the truck.



-brian

 

[MMiller]

Brian, maybe the rear tires on your 90 had D rated tires= 50psi. Read what it says on the sidewall of the tire. Air them up as close to that spec COLD for best wear/life out of them.

Bill, the cold spec on the tire is for the max load. That does not mean to air them up to that pressure if you just have an empty truck. No tire will wear correctly on the rear of an empty truck, it inflated to max pressure. It will only wear down the center and have very unpleasant ride, and poor traction in all conditions. The wider the tire the more prevelent this will be. If I ran my rear tires at 50 psi all the time,I would only wear the center 2" of the tread and the rest of the 12" tire would be new.



Now, Brian, you did not mention how the tire was wearing on the rear? Is it wearing more in the center, on the edges, or just one edge. Go buy a tire tread depth gauge and get a good idea how the tire is wearing. Just by chance is the right rear wearing the fastest? Just because you don't spin the tires on purpose all the time, does not mean the cummins isn't eating them up. My truck will put down two black marks on the pavement when taking off with the trailer, not spinning, but indeed the tires are wearing when I do this.



I run a wider tire, and set the fronts at 45 psi, and the rears at 35 psi when empty, or lightly loaded. This keeps all the tread on the ground for consistant wear. I pump the rears up to 50 whenever I pull my trailer. I know is a pain, but so is buying expensive tires when I don't need them.



Michael

 

[btoscano]

My current W250 is wearing the rear tires evenly by eyesight. After 8000 miles, they are about 3 fingerprint lines lower than the front ones. How's that for a tire depth guage ???



-brian