05RX330AWD

The door label indicates 30 psi, I'm at 32 psi although thinking more along the lines of 34- 35 psi to cool the tires more.
Just wondering what psi CL Members are using for cold inflation, 18" factory rims, 235/55/R18 tires for summer weather.

takeshi74

I aim for about 35. 30 is just too soft for me but I'm used to driving sports cars. 35 doesn't make the RX a sports car by any means but it helps a bit IMO.

05RX330AWD

Agreed, I do not drive as if I stole the RX although I found handling disappointing at 30- 32 psi....
especially at a roundabout.
Also looking for possibly an improvement for MPG at a cold 35 psi, which translates to about 37-39 psi on the road. The tires indicate Maximum 44 psi.

davintosh

I was thinking that 30 felt too soft; glad to hear I'm not the only one who bumped it up a bit. Have you had any tire wear issues at 35 psi?

05RX330AWD

Too early to tell although I was more concerned that at 30 PSI, the sidewall of tire will soften more with the summer heat, if you inflate the tire with more air, it cools the tire a little more.
Either way, no perfect solution, prefer more normal, accelerated wear than the sidewalls weakening, plus the handling has improved.

DennisMik

I tun my fronts at 35 and my rears at 32 year 'round. I can feel the ride getting harsh at higher pressures.

05RX330AWD

The ride is definitely harsher, you can really feel a difference when jumping from 30-32 psi to 35 psi the first day.
After a few days, I suppose you get more accustomed to the ride.
Of course, the preferences from RX drivers will vary...
there are no perfect answers.

davintosh

Did bumping the pressure up have any effect on gas mileage? Ours seems to be consistently ~24 mpg on the highway, and ~22 around town.

DennisMik

Higher air pressure does give better gas mileage. Having lower air pressure creates more rolling resistance because of the sidewall flexing (or bulging). But for the 5 psi that has been talked about here, you may not be able to tell any difference.

05RX330AWD mentioned higher pressure will keep the tire cooler, which is a very important consideration. Besides rolling resistance, sidewall flexing causes heat buildup, which is will cause the tire to fail. I'm sure that you have seen the tire treads from the semi-trailer trucks laying alongside the road. This is the result of the tire being under-inflated.

I like to keep my tire pressure a bit higher than the factory recommends because the tire wears better, which lets me get more miles out of it. It's all personal preference.

05RX330AWD

FWD or AWD? with AWD, so far, after only a couple of days, my experiment with 35 psi is showing 16 MPG in City, stop & go driving conditions.