I am running Nitto 555 tires, 255/35/20 front and 275/35/20 rear. What is a good air pressure to run for street use?

 

Street use? Its probaly written on the side wall of the tire, go check.

 

No, only the maximum air pressure is listed on all tires.

 

Your 255/35-20's have the same load index rating as the OE 235/50-18's, so you could use 32 psi there. I'd tend to fudge that up two or three psi for a little extra rim protection - watch your center tread wear, though.

The 275/35-20 has the same load index as the 285/40-18's as found on the GT500, so you can use the GT500 rear tire pressure directly. I don't think you need any more pressure there for rim protection. You'll have to find out the GT500 pressure on your own, or maybe somebody else knows it off the top of their head (I don't).

After all that, drive it and see if there's anything about the way it drives that you want to change a little.


Norm

 

Thanks for the info. Norm. I ran 31psi front and 30psi rear for 2000 miles and noticed about 1/32nd more tire wear on the edges (as compared to the center of the tires) of the fronts, and .5/32nd more edge wear on the rears. I have changed the pressures to 34 front and 32 rear to see how the tires do.