traded my 18's for 17's - Toyota Nation Forum : Toyota Car and Truck Forums

fredberg · 08-27-2007, 10:33 PM

i traded in my 18's for 17's. u prob think i'm nuts, but i'm actually loving the better ride comfort and lesser roise. the difference is pretty amazing, considering i only changed to 17". i was running 225/40/18 tires.

anyways, my question is, what psi to run at now? my tires are 215/50/17. i was running the 18's at 36psi. jus needed some opinions for the 17's. thnx!

white3ch0c0late · 08-27-2007, 11:14 PM

Uh... run it at 36psi.

Tire size and tire pressure have very little to do with each other. Having larger tires only means that you can get more air into the tires, but the pressure is relative.

fredberg · 08-27-2007, 11:33 PM

Quote:

Originally Posted by white3ch0c0late

Uh... run it at 36psi.

Tire size and tire pressure have very little to do with each other. Having larger tires only means that you can get more air into the tires, but the pressure is relative.

ok, fair enuff. but going with that idea, my stock tires were 205/65/15. the recommended psi for them was 29. does that mean any tire use shuld be at 29 psi as well? granted that i match the overall diameter to OEM?

i'll run it at 36 psi for now...

TRD VVTi · 08-28-2007, 12:05 AM

I'd run as high a pressure as you feel comfortable up to the maximum pressure on the sidewall of the tire. Most FWD cars wear on the edges of the tires in general so higher inflation will help with the wear in most cases. It will give you maximum fuel economy also.

bike4miles · 08-28-2007, 08:39 AM

Tire presure is not to be taken lightly. A tire with less volume needs more presure to support the wieght of the car. You should NOT have to run as much presure with the 17's.

Not convinced of this fact anyone?

Here are some examples: A bicycle with 23mm road tires needs 100psi while a mt bike with 2.5" tires needs 35psi to support the wight of the same rider.

My 4runner needs 28 psi in the tires and my maxima with low profile tires needs 35 psi

You need to go by the recomended prsure on the tire sidewall. This is calculated by the manufacturer baised on the intended use and the tire volume. You may have to run at the upper or lower end of the range given depending on the wieght of your car and driving conditions (remember heat causes presure to increse and extreme cold causes the presure to decrease).

johnnyzee · 08-28-2007, 12:18 PM

to answer your question before this thread gets out of hand, 35-36psi buddy for your 17's or 18's. i dont know where you heard 29 but from my experience (worked in a tire shop for 6 months back in high school) 32 is the bare minimum we'd ever do, and that was for a softer ride, but would wear out tires a bit sooner. pretty much every tire we filled was at around 35psi.

TRD VVTi · 08-28-2007, 04:50 PM

29 PSI comes from Toyota as a recommendation. Those numbers are located in the driver door jamb.

There are no tire pressure recommendations on the sidewall. The tire manufacturers couldn't possibly know every application that the tire is going to be used in. That's why the put a MAXIMUM pressure on the sidewall.

I personally never run less than 30 PSI and sometimes run my pressures at the max. Usually I'm at 35-40 PSI.