Originally Posted by dkstone05

Too early in the morning....I'm the OP

Originally Posted by dkstone05

I checked my tires this morning and they were at 46psi...not the 50psi the shop put in. However the air temperature when installed was around 45 degrees and this morning it was 32 degrees. So I guess this explains the 4 psi difference.

Originally Posted by dkstone05

but the shop uses nitrogen and I thought that nitrogen wasn't supposed the change that much with air temperature?

Anyway for giggles I took them down to 44 psi just to see what would happen on my 20 mile commute to work. Once I got to work they were just a shade under 50psi after the 20 mile hwy drive.


If used the calculations I think I would be in the mid 30's psi but this is very rough as I'm not sure of the weight of my truck let alone weight per axle. I think I feel more comfortable with a minimum of 40-45psi for an general air pressure with out needing to air up for loads as an air compressor isn't always easily accessible. This unless I see excess wear in the center.

Originally Posted by Galaxy

Not really. On average, there's a 1 psi difference per 10 degrees. This is less aggrivated the bigger the tire.




From what you've said here, I'd be willing to wager your tire shop didn't use the nitrogen. Also, don't forget (now that you've aired your tires down) if you add air to pump them back up any, the benefits of the nitrogen are negated.

There was another thread on nitrogen not to long ago...lots of information but I'll summarize for you; not worth it.

Originally Posted by dkstone05

I'm not concerned with nitrogen at all. This shop says that all they use as a default. Possibly my pressure gauge is off which I have a couple more laying around to check against.