Tire Pressures

[hpracing10]

2003 halfton silverado Z71- I have Load range E tires on it, so they are 10 ply. The sidewall calls for no more than 80 psi cold, but of course we all know not to run tires at the rated pressure as that is wayyyyy too much. I have them at 45 psi cold, and the centers seem to be wearing out faster than the outside edges. they are all terrain tires, actually they are Hercules Terra Trac A/W tires. With 45 psi they are squatting down pretty good and the whole surface of the tire is touching the ground, not up on the edges or anything. Why are they wearing faster in the center than the outsides? I don't really want to go any more lower because I think they are already low enough, if not too low.

 

By the way, the truck has been kept properly aligned for the life of the tires and they were balanced when new and are still balanced fine. I rotate them every 5K miles also. The tires have around 35K miles on them of about 85% highway and 15% off road. They look like they could still go another 20K but just want to figure out how to make them wear evenly.

[Matt_]

Drop the pressure to 40 PSI. 35-40 is ideal for the weight of the half ton trucks... i'd run the fronts at 40 and the rear at 35. (then bump the rear up to 50 when towing)

[mipsco1]

yeah if they’re wearing in the center the pressure must be too high.

[WaterGuy]

I run all 4 at 80 all the time.

[mipsco1]

I run all 4 at 80 all the time.

 

 

you also drive a 2500

[ryan_hermanutz]

Draw a line of chalk across the tire from shoulder to shoulder and then drive in a straight line until the chalk starts to wear off. Ideally you want the wear to be even all the way across, if it's not, adjust your pressure up or down until it is.

[Matt_]

I run all 4 at 80 all the time.

 

 

you also drive a 2500

 

 

still doesn't make it right. Most 2500s should be at 50-55 when not loaded. I think the 2500HD DMax's have a higher unloaded spec due to the engine weight... but it's still around 60 PSI. There's absolutely no reason to ever run 80 in a 1500... and the only time a 2500 needs that is if its a 2500HD loaded to max capacity.

[hpracing10]

Thanks for the quick respones everyone, I am headed out now to drop the pressure down to about 40 in the front and a little less for the rears. I'm hoping this helps. They look like they are squatted a bit right now, dropping them down even further won't hurt anything? Thanks again

[Matt_]

You can't tell if the tires are properly inflated by the amount they're "squatted". I used to get cars in the shop all the time with 70+ PSI, in car tires that have a max of 32 btw, because people would inflate them until the "bulging" went away.

 

It's perfectly fine to run 35-40. Remember this is "COLD" psi. The tire pressures will increase 3-5 PSI just from driving around. On the other hand, if you drop them to 40 PSI while they're hot, they'll decrease to 35 PSI when they cool down. So make sure you set them at 40 when they're cold and you'll be good to go

[brims]

I don't know how many people have told me "your tires are low on pressure" just by looking at them, the front tires have a little buldge but wear perfectly.

 

I like the chalk line idea.

[Ryan00TJ]

Chalk line works pretty well. I've used it before on my TJ's swampers to get a decent wear pattern from them on the road. Need 24psi to wear evenly. I've been running 45psi in my 245 C rated 17's just like the door sticker says and after 8K miles they are wearing very evenly.

[Zembonez]

HOLY CRAP! 80 psi is nuts in an unloaded truck. It must ride like a covered wagon on cobblestones. 35- psi is PLENTY of air pressure 4 ply, 6 ply or 20 ply. More is recommended when loaded on HD rigs, but a half ton should never see over 50 psi.

[minibike132]

HOLY CRAP! 80 psi is nuts in an unloaded truck. It must ride like a covered wagon on cobblestones. 35- psi is PLENTY of air pressure 4 ply, 6 ply or 20 ply. More is recommended when loaded on HD rigs, but a half ton should never see over 50 psi.

 

Agreed, I have an issue with the way TPM is set up on Hd's because of this. The sticker on a 2500 is somewhere between 75 and 82 depending on the setup. The law is that the light comes on 20% below recommended pressure. That means if the sticker says 82 the light will come on at 64psi which is way too much for an unloaded rig, that thing is going to be bouncing down the road which is unsafe. Not as unsafe as a blow out but unsafe none the less. There is absolutely no need for 80psi on an unloaded truck, 35 should be fine just make sure you put some in before loading up.

[nelson.jones07]

I also think the same at 2500. Thanks for the help.

[asilverblazer]

35psi is what 1/2 ton trucks are rated for and that is on passenger tires.