tire pressure for 255/40r17
 

im picking these up tomorrow and want to know what pressure i should be running them at. according to this chart https://www.toyotires.com/media/2125...s_20170203.pdf it says <26psi which seems way fucking low. if my math is right and it has the same contact patch size but just 40 mm wider i should be running somewhere around 29.5 psi

That's just for equivalent loading. You can run the same pressure as OE (35 psi) and be confident that the car can handle the same load with extra margin.


Also, if you run TMPS, the car is going to throw you a low tire pressure code anytime you're under 30 psi anyway.


The concept matches up whether you use P-Metric or ISO-Metric measurements

wouldnt that mean it has the same size contact patch as 215s?

No.

I always use the pressure what's on the door sticker. Regardless of different tire size or brand. I never had any abnormal wear or any other issues.