luckydawg003

What Psi should I be running in my Nitto Invo's. Front are 255/45/18 . Rear are 275/40/18. I had the fronts at 32 and rear at 36, but the tire shop guy bumped all four up to 50 psi. I think thats too high, but not sure since aftermarket tires don't tell you what psi to run them at, only the max is listed.

What psi should I use?

Nuke

What I do whenever I buy new tires is start with what's on the door placard and work up or down from there in 2 PSI increments. Since I prefer a bit of over-inflation from what's recommended, I'm usually at about 2-6 PSI above the placard but it usually depends on the tire and how I'm driving it. At 50 PSI, your "footprint" is likely limited to the 1/2 - 2/3 of the tread width from the center. The guy at the shop is a moron.

Derf00

+1 on almost all of it.

The dude at the shop should not be working there. I bet the 50Psi he put in was the MAX listed on the tire?

AMWill

I agree with these guys ^^^. 50psi is the max rating for the tire and NOT what you should run at any point in time on the street. I would stay around 32psi for both tires. You can move up and down from there until you find something you like, but not too much higher.

Hope this helps!

Shane