whenever the tires heat up and get to 38psi the "check tire pressure" comes on. when it's cool and below 38psi it is fine. anything the dealer might be able to do? i am running my tires at 34psi but want them at 35-36 cold

 

your tires are runningat a higher psi than the factory recommends so naturally when they get warmer your getting into the upper limits of the sensors, thus causing the light to come on.
Two things:
1. I had my dealer set my limits on my 24's to set off the warnings when the psi's get downto 32 psi. I run 33-34 psi in my tires for the load and the best ride for my brandtires. I know there is some type of adjustment that can be done, but Im not to sure if they will do it at customers request for liabilty reasons. We do a lot of work for my local dealaership so they take care of us. Im not sure if its a preset program or if they canthey set the specific psi. I just asked it I could get it to set off around 30psi and 32 is the number the lights come on.
2. Run Nitrogen 98% fill and your PSI shouldnt fluctuate keeping the light from going on....

 

If i run nitrogen itshould stay at what the psi is set at? warm and cold

My factory sensors went off after heating up and raising to 38 psi. the new ones in my 24's doing the same thing so i will see if the dealer can change it. Thanks

 

yes to the nitrogen staying the same. Nitrogen can lose and gain psi but at a much much much muchlower rate than air. The higher % ofnitrogen fillthe less chance of fluctuation.

 

I run my stock tires (20s) @ 33 and they run 38-39 w/o setting any warnings. Maybe I'm not understanding the problem tho.

 

my 24's cold are at 34psi and when they get hot go up to 38 and set the dash "check pressure". just kinda bothers me

 

Not sure why that would be happening. Maybe should have dealer check. I'm assuming that the max rating on the tires isn't around 40 psi. If it is, maybe the installing dealer reprogrammed the TPS for that.