Bought used 2009 Express 1500 that was fitted with P rated tires with a max pressure of 50psi. Replaced them with LT rated tires with a max pressure of 80psi.
The dealer wants $125 to recalibrate the TPMS system. Is there a way for me to adjust the normal pressure amount?
Thanks.

 

Someone correct me if I'm wrong, but its my understanding that the TPMS has nothing to do with anything except letting you know the tire pressure with its relative tire. That, and illuminating the dash indicator. So, who cares? Put a piece of tape over the icon if it bugs ya. When its time for inspection or smog check, lower the TP to the level that the monitor is calibrated with. Just sayin

 

that is the going rate to perform this job. You can't adjust this without a scan tool that can access the module...either the ebcm or ddlm.

 

But you shouldn't use a higher pressure. Chevy has determined the correct pressure by figuring the weight capacity of the van.

Edit- Seems to me that LT tires are the correct tires in the first place. Why would the PO change out or reprogram the TPMS sensors? He probably went with P tires to save money, and changing the TPMS might cancel out any savings.

Just sayin'.

 

You don't need special tools. Just letting out some air is enough to recognize/relearn a tire.

 

'P' tires will potentially give a nicer ride. As long as you meet the load/speed ratings, I don't see why it would be a problem.

My 1500:

 

You should have just put p rated tires in my opinion. Factory tire specs are designed for that van. The lt 10 ply tires have a stiffer sidewall for loads you will never carry in that van. Also you get better fuel economy on the passenger tires.

As for your situation, are you getting an error message for over inflation? Another option is to replace the tpms sensors with the right ones, since the batteries in them don't last forever, and yours are 10 years old....

Also, its 50 psi for the fronts and 80 on the rears if you have the higher gvw 2500 or 3500 vans.

 

He can run those tires and still keep them at factory pressure settings. Would probably help with ride quality.

Vehicle specs for tires and/or pressures are indeed part of the equation. Changing from OE spec tires isn't a problem and new TP can be calculated to at least bring Weight ratings for front and rear back to par. However, this may be higher or lower than the TPMS sensor and give a dash light.
I have two tire pressure formulas but posting them here would be drifting off topic . One is easy, the second is a bit more math but not bad.

 

the op is referring to changing the pressure in which the tpm triggers a warning...not learning the sensor. this requires a change in the module set up.
LT's are a better tire. I would prefer them over a p tire. I mounted and balanced quite a few over 17 years...Lt's balance with less weight and have less runout.

 

If he bought them for looks then the OE pressure is fine. If he's gonna use them to take advantage of their higher load rating, then a recalibration would be in order. A part of that equation is how much GAWR will there be.
I agree about the LT tires. They make some nice ones.
My OE new tires have a 110 load rating and are just fine for this application.
Hopefully the OP can post a few pic's of what he chose.