I used Bimmercode to have the OBC show the temp as well as the pressures.
Just did a long trip and started to get a little OCD on temps and pressures.
I don't have runflats, but still run 35PSI cold.
During the trip I saw pressures as high as 43PSI and temps as high as 113F Ambient temps were never over 75F.

Anybody have thoughts on 'normal' ranges? I always thought tires added 4-5PSI at working temps. Tires are rated to 50PSI, so not near their max spec.

 

I've had that coding activated for a couple of years now. I also don't use runflats. On my car I've never seen tire temps on the display higher than 115, and even that was on a day when ambient was well over 100 and it was a highway trip. So I feel like those temps are abnormally high. But I wouldn't worry about it ... a decent V-rated tire. or higher can take temps well higher than that without any ill effects.

But pressures -- that kind of increase is not really abnormal. It's likely that the air in your tires has a fairly high water content, which leads to greater increases in pressure with temperature (this is the only argument for nitrogen in tires, not that it really matters for average street use). This is the #1 argument for using nitrogen in race tires -- and I raced for many years. Nitrogen is dry and that leads to much better predictability of pressure increase with heat. But I don't use nitrogen on the street and. I certainly wouldn't be concerned about tires at 43psi hot.

 

It's called 'friction', an active heat generator. Another thing, like mileage, I don't waste my time thinking about while just enjoying the ride.

 

Came to it honestly. One tire started reading 1.5lb low, I was going through Death Valley w/o runflats and my little compressor just died, so I was a bit anxious. Also noticed that the temp didn't always correspond with the pressure. Then got to wondering how accurate the sensors are.