executionereric

I was getting an oil change recently, and have after market tires and rims.

The pressure rating on the tires says 80 PSI max for my 4X4, but since the tires
were aired to 37psi the last oil change, and I decided to brinbg them up to 55psi.

Now the check tire pressure light keeps coming on.

Why did the tire pressure light not come on at lower pressures?
And if they need to be lower, why do the newer tires say max at 80 psi>?
Seems kinda high to me, since I have never seen a tire PSi that high.

Also, if I inflate to lower psi, such as 37, the tire looks to be slightly bulged at bottom
as if there was not enough air in the tire.

If anyone has experienced this please post here.

charlie pachanga

Sounds like you have 10 ply tires, load range E. If they are load range E then they usually require higher tire pressures. If you have lower tire pressure they look bulged. Check your tire placard for tire pressure settings. The tire pressure system lights up when you have a +/- 25%difference.
The dealer can change the tire pressure systems threshold to work with the tires you purchased, check with your dealer.

executionereric

Ok,
Thank you for your reply.

You were absolutely right!
I have 10-Ply Bellted Radials, and apparently they were designed for the 2500,
and the proper install for the 1500 requires a visit to the dealer to tell the
internal computer that you will be using higher pressures than the default,
which is listed inside the frame of the driver's side door at 35psi.

I opted to keep the larger tires and the dealer reset the computer with
a pressure rating of 40psi, which will give me less bulge at the bottom of the tire.

There are some people that say you can re-learn the internal tire locations and pressures
by yourself, which is inaccurate in this situation, because by resetting the internal psi
reader you only manage to bring the sensors within the recommended manufacturer's setting,
which is again 35psi. So be very careful NOT TO RESET THIS yourself.

If you take it to a registered chevy dealer the cost to refresh the setting at the higher psi is only $20.
I went to Town and Country Chevrolet in Milwaukie, Oregon.

Also, be aware that most tire shops DO NOT KNOW HOW to do this update, and they will burn you
by putting only 35psi in the tire to get you off their lot, which ensures that you will visit them in the future.
And when you do decide to visit them in the future they will try to either sell you new tires, or just send you
to the dealer after you wasted an entire day trying to trace the problem. Don't try to fix this yourself!

Spend the $20 at the dealer and save yourself a large headache.

SuperTexan

You have to get this reset when you do rotations too. Not the pressure, but the locations of the wheels. Also the valve stems must be rebuilt on each flat repair and new tire install. Make sure this gets done.

Charms

The tire business is a very tough one to be in.