Ok, I asked this question in the "Why you should get 255/40-17 tires for your OEM rims !!!" thread, but no one has been on there in a couple of days, so here it is:

I recently put 255/40s on my car, and adhered to Inaccurate's pressure recommendation (35 front, 30 rear). At about the same time I mounted the tires it started to get cold out here in Montana. My TPMS has started showing low PSI in all 4 tires (~30 front, 26 rear), but the rears are indicating low enough to set off the "alarm". I know cold air will drop tire pressure a couple PSI, but when I checked with a real guage, all 4 tires are still right where they were when I mounted the tires (35 psi front and 30 rear).

My question is do these sensors/system "go bad" over time? And I was wondering if it was a result of the wider tires, but I doubt that. 35 psi is 35 psi, regardless of the volume of air inside the tires, right?

Thanks for any help.

 

Did you try a different gauge?

 

2 different ones. A normal one and a digital one, both gave me the same reading: 35 psi front, 30 psi rear