Changing PSI?

[ArabianKnight]

I have been to a couple service shops lately and the PSI in my tires First a Valvoline shop put at 35 in Ohio, then I had my brakes serviced in TX and when I check them they were at 40 PSI! Before I went to get them serviced I deflated to 30 PSI. It clearly says 30 on the door jam, I am using OEM Goodyear Wranger AT/S at about half worn. Its an 04 Z71, am I missing something here? I prefer a softer ride and the max PSI is 44 for these tires. What gives?

 

[BRUTUS_T_HOG]

Inaccurate gauges. Or they just don't care about the door jamb spec.

 

[Badmunky]

Door spec is what the manufacturer recommends based on the best compromise between Ride quality, tire life, performance, and fuel economy.

I prefer tire life, performance, and MPG over ride quality. So I run higher pressures in my tires.

If you value ride quality then run lower pressures.

I run 42psi front, and 38psi rear. When towing I up the rear to 42psi.

I use a digital gauge I got from Summit Racing a few years ago. Cost me like 85 bucks but it has been the best one I have ever had.

 

[Chiggy]

Don't forget that temperature makes a huge difference in air pressure. A tire at 40 psi in 70 degree weather will drop to around 30psi if the temp drops to around 30 degrees and that's just ambient. Driving makes them heat up as well. Do some driving and have them checked and they are at 40psi, let it sit and the temp cools down outside too, I could see them dropping to 30psi easily. I don't have the factory tires on my tahoe but I'm running 42 psi. I like the responsiveness and MPG's

 

[Yukongk]

Ya, always check them cool (before driving) and at the same time in the day if possible. I think for every 10* difference, tire pressure goes up/down 1 psi.

 

[Goodinblack]

I run 38