Stu

I believe Lexus recomends running 33 p.s.i. for the front and rears ....

Does anyone run higher tire pressures than 33 ?
What is the reason and benefit of running highter pressures ?

GeorgeT

I usually run 34-35 psi. Higher psi improve handling but you lose some ride quality. Aslo, higher psi will yield slightly better mpg's.

jayclapp

I didn't buy my Lexus to get good fuel economy. Not a consideration.

m3nv

I leave mine at about 32 psi. Car still rides like butter

fergo308

There's not really any benefit to be had from raising tyre pressure more than a pound or two above recomended levels.

Your mileage may improve by a tiny fraction,but you'll also lose a little grip and steering feel.


Justin...

CarGuy89

A few more PSI should be added if you live in colder weather (if we consider the ideal gas law PV=nRT), once temp drops, your pressure in your tires will drop. Do the opposite for hot weather. As long as you don't exceed the upper pressure end of the tire itself it really should be too big of a deal. Varying the pressure slightly won't do a whole lot.

Bocatrip

I have V rated 225/55/17 Primacys and the recommended tire pressures are 35. I keep them around 36-37. I believe 33psi are for H rated tires.

tsslaporte

I keep all the tires of our cars are 35psi(cold)

The Doar Jam psi is just a guide, many tires will perform better are a bit higher PSI.

For instance when I had the Eagle RS-A tires on my G. In the wet at 32psi under moderate braking ABS would kick in and scared the heck out of me since they broke loose very easily. I pumped the fronts up to 38 since I went to the track and just left them at 38 to see if it made any difference(50psi is sidewall its perfectly safe), and wow water traction was severely improved, but still sucked heh.

Jabberwock

The ideal PSI on a specific tire would maximize contact patch profile while providing sufficient stiffness and support to the sidewalls (and maintaining the bead seal).

I think at some point raising the PSI on a tire causes the foot print of the contact patch to crown (become round) changing and reducing the contact patch's profile with the road. The point where that happens and negatively affects ride and handling is different for all vehicles based on weight and weight distribution of car. I would guess that ideal PSI might be slightly different between front and year axles on most cars.

GRAND_LS 4

iTrader: (2)

Its actually based on the car and its weight, not the tire itself. I would follow the recommended tire pressure +/- 2-3 PSI depending on type of road and personal preference.

abs

+1

Lust4Lexus

When I first came home with my new primacies, I noticed how much more controlled the car was, especially in the rear. I loved it! When I got home I checked the pressure, to find that lexus had inflated to about 38 psi, b/c my car was at 40psi after the ride home. I lowered it back to the stock reccomended 32. With the primacies, it turned into a boat. 35 is what I run as a compaimise.