I was just curious to see what all tire pressures people out there are running with 17 inch wheels with 275/40 out back and 245/40 up front. I know stock is like 30 sum, but the tires call for like 60 max. What should I be running?

 

It depends on the brand and quality of the tire. Pressures can varry greatly between two different brands of tire both being the same exact size. For instance, I ran 49.5 hot fronts and 46psi hot rears with the GSd3's and I run 44 front 39 rear on the crappy BFG KDW tires that are on it now. Ambient temps spped and air moisture can directly have a result also in pressure differences. Moisture inside a tire will heat up quicker and grow the PSI faster and higher when the tire gets hot.


I happen to have the unique fortune of being an avid SCUBA diver and have a resorceful supply of dry filtered air bottles to fill my tires with. Dry filtered air is even better than standard nitrogen. Even nitrogen has moisture in it. The advantage of nitrogen is the tires will not molecularly blled air off as quickly through the rubber as air will. Nitrogen has bigger molecules. Dried, filtered Nitrogen is best for maintaining daly tire pressures and consitant wear with better longevity as a result.

 

245/45-17 kumho's i used to run 40 street and 25 strip..

 

Well, I have the Kuhmo Ecsta ASX All Weather tires if that helps any.

5678TA- That is actually what I am running right now in all 4.

Any one else have any input?

 

Well, when I went from the 205's to the 245's I ran 35# in the fronts and rears. The max pressure on the sidewall was 45#. After a lot of miles (i don't remember how many) I noticed that the center of the tire thread was wearing faster then the outer edges and the tire was not good in the wet. I guess if you think about it the larger tire will carry a lot more weight then the 205's. I was just going to lower the pressure and keep a close eye on them but I figured that would take a long time so I decided to use chaulk. I found a nice flat piece of road (not easy to do) that had a nice long streight away. I then chalked a wide band accross the tire and went for a ride. I started at 35# and ended up with 26# in the front and 24# in the rear. Man what a differance in the wet and all around handling. Pretty crude method but worked for me.

Auggie

 

thats cool.. when i had my kumho's and 17's, i would just skate all over the place.. damn rock hard tires.. couldnt get them to squeal until you hit them with a huge burnout.. i ended up just running the 25 on the back with those until i got 3" wheel studs..

 

I guess I will just have to play around with them until it feels good. Thanks.

 

On my 245/50/16 kumho ecstas(awesome road tyres) i run 34 front and 30 rear and get good tyre life and none of that inside edge wear of the fronts that i used to get when running 30 in the front.

 

32 to 35 PSI........