What is the optimal tire pressure for max tread life? For a long time I thought it was setting the tires to max psi, but was then told by a tire tech that this will cause the tire to wear out the center faster? My max tire pressure is 50psi, he recommended 36 for tire economy. :confused:

It's a soft 200-tread rating summer tire if that matters.

Edit: Mod please move to correct forum. It's been one of those days...

it depends on the driving style, and the alignment specs.

And the tire, too.

It is, without a doubt, NOT the max pressure shown on the sidewall. To find what the actual pressure that's best really is, though, just takes experimentation.

Pat

And the tire, too.

It is, without a doubt, NOT the max pressure shown on the sidewall. To find what the actual pressure that's best really is, though, just takes experimentation.

Pat

That's it - try a different one in each tire and then don't use the one that shows the most wear. :devil:

Really, why would you buy a 200 wear rated tire (I read that as performance) if you are concerned about mileage? If you find yourself stuck - drive VERY slowly around turns and do not brake or accelerate quickly - they'll last 25k or more

Really, why would you buy a 200 wear rated tire (I read that as performance) if you are concerned about mileage?
Good mileage and good performance are not mutually exclusive. I got about 33,000mi out of a set of Toyo T1-S, including 4 days on track, and around 30,000mi out of the last set of Goodyear F1GS-D3s. A good alignment and proper tire rotation goes a long way.

By your logic anyone that wants performance tires should just drive on R-compounds. After all, mileage shouldn't be a concern if you want performance tires, right?

Pat

I agree with Patrick, but im not getting involved in this fight. From what ive read about tire pressure for subarus, most run more in the front tires to help with handling a little. Say 40/36 F/R.

I agree with Patrick, but im not getting involved in this fight. From what ive read about tire pressure for subarus, most run more in the front tires to help with handling a little. Say 40/36 F/R.
I tend to run more in the rear on my wrx, but that's my preference in handling and feel.

I could have it backwards, i just remember reading that some where.

.....there is NO answer to this question....but somewhere between ~20psi and ~50psi will yeild the best results, no doubt

Good mileage and good performance are not mutually exclusive. I got about 33,000mi out of a set of Toyo T1-S, including 4 days on track, and around 30,000mi out of the last set of Goodyear F1GS-D3s. A good alignment and proper tire rotation goes a long way.

By your logic anyone that wants performance tires should just drive on R-compounds. After all, mileage shouldn't be a concern if you want performance tires, right?

Pat

My logic was only that a tire with a 200 rating was not a run of the mill tire. Scotty has it - there is no answer. Lots of things determine how long a tire will last (some cars are hard - my 3000gt vr4 was bad I heard nsx's are hard) but I think driving style is the biggest factor. I have asx for the harsh California winter and my 070's for summer. If I tried real hard I could wear out the Kumhos faster inspite of their 420 rating. Or I could make the 070's last but why for both?

All I was really saying was - why would one buy a tire with a 200 rating if one was concerned that much with wear?

All I was really saying was - why would one buy a tire with a 200 rating if one was concerned that much with wear?

Perhaps he doesn't have money to waste buying tires needlessly and wants the best life possible from the choosen tires? Just because he wants performance tires doesn't mean he wants to replace them twice a summer.....

Are they stock size wheels?

If so,...it is almost always the case that the pressures given by the manufacturer (usually on the drivers door jamb) are the best for tire life. On my 04 STI that is 36 ft and 32 rear.

Larger rims with lower profile tires usually want higher pressures. The idea for tire life is to have eaqual pressure on all parts of the tire. Lower profile tires have stiffer sidewalls, so you need more air pressure to force out the center of the tire and make the force on the tread even to the ground.

Best performance is different altogether. Best grip will also usually be the factrory pressures, but under hard side loads (hard turn) the tire will deform off to the side and the tire will loose traction. Higher tire pressure will resist this, and keep the tire squarely on the rim and flat on the road. This will more than make up for the little bit if traction lost by the decreased contact patch area that raising tire pressures will cause. So for a very twisty road or race track, you always want to bump up the pressures. Try 10psi over what is on the door jamb to start with. Then, if you have a probing tire purometer,...you can test the tire just after pulling in the pits and adjust the presure from there.

Best mileage is indeed high pressure,...but that WILL bow out the tread in the middle and make the tire wear out in the center more. If you always inflated your last tires to a certain pressure and they wore out in the center first,....lower the pressure for this set. And visa versa.

Best pressure for max tread life is whatever allows the tire tread to wear evenly across the width of the tire.

Too low, you wear out the outer tread. Too high, you wear out the center tread.

Every tire/wheel/suspension combination will require a different pressure. FWIW, i run 36f/33r on my OEM sized tires/wheels. Simply monitor how the tread is wearing at each tire rotation and adjust pressures and necessary. You do rotate your tires regularly right? Right? ;)

Best pressure for max tread life is whatever allows the tire tread to wear evenly across the width of the tire.

Too low, you wear out the outer tread. Too high, you wear out the center tread.

Every tire/wheel/suspension combination will require a different pressure. FWIW, i run 36f/33r on my OEM sized tires/wheels. Simply monitor how the tread is wearing at each tire rotation and adjust pressures and necessary. You do rotate your tires regularly right? Right? ;)

That's how I set my pressure. I usually fill the tires a bit high and observe the tread to see how much of the surface is contacting the ground and bleed 1-2 lbs at a time. Since I'm a bit agressive my tires are usually a couple lbs higher than Psydotek, 39f/35r.

Best pressure for max tread life is whatever allows the tire tread to wear evenly across the width of the tire.

Too low, you wear out the outer tread. Too high, you wear out the center tread.

Every tire/wheel/suspension combination will require a different pressure. FWIW, i run 36f/33r on my OEM sized tires/wheels. Simply monitor how the tread is wearing at each tire rotation and adjust pressures and necessary. You do rotate your tires regularly right? Right? ;)

This is the correct answer.

One you find out what pressure gives even wear...alter it a few pounds either way to tune the handling. I run 42f/38r...the WRX is heavier in the front than in the rear...and therefore need more air in the front to keep tha same contact patch as the rear. Running OEM 16's with Avon Tech M550s.

Generally you will attain optimal tread wear by using the pressure specified by the vehicle manufacturer (see the VIN plate in the d/s front door jamb area). If you set the tires to the max pressure indicated on the sidewall, you may experience accelerated tread wear in the center of the tire since it is over inflated (the center of the tread contact patch tends to balloon out-which causes this). Conversely, if the tires are underinflated they will wear the areas on the tread patch closest to the sidewalls faster since they are riding more on the sidewalls themselves. The air pressure specified by the manufacturer applies to the stock size tire. If you have changed sizes you should consult a reputable tire dealer (like Tire Rack) for advice w/regard to proper air pressure settings. Always remember to check the tire pressures when they are cold (before doing any driving)! When they are hot (after driving) the air pressure when checked is higher than it actually is, so the reading is not as accurate.

Generally you will attain optimal tread wear by using the pressure specified by the vehicle manufacturer (see the VIN plate in the d/s front door jamb area). If you set the tires to the max pressure indicated on the sidewall, you may experience accelerated tread wear in the center of the tire since it is over inflated (the center of the tread contact patch tends to balloon out-which causes this). Conversely, if the tires are underinflated they will wear the areas on the tread patch closest to the sidewalls faster since they are riding more on the sidewalls themselves. The air pressure specified by the manufacturer applies to the stock size tire. If you have changed sizes you should consult a reputable tire dealer (like Tire Rack) for advice w/regard to proper air pressure settings. Always remember to check the tire pressures when they are cold (before doing any driving)! When they are hot (after driving) the air pressure when checked is higher than it actually is, so the reading is not as accurate.

Someone correct me if I am wrong, but I believe manufacturer's indicated tire pressure is set to meet load requirements, offer comfortable ride, prevent unpredicatable handling but are in no way optimized for tire life.

Would optimal tire life within specific alignment/drivingstyle/etc be optimal when tire pressure is set for even temp readings?

I have an IR temp sensor and I found that for commuting, my tires seem to prefer 37 psi front and 35 psi rear for even temps out/middle/in.

Moving from Suspension to Tire/Wheel

Would optimal tire life within specific alignment/drivingstyle/etc be optimal when tire pressure is set for even temp readings?

I have an IR temp sensor and I found that for commuting, my tires seem to prefer 37 psi front and 35 psi rear for even temps out/middle/in.

i would say that if you're equalizing temps across the tread(s) you're equalizing wear as well, since the temps are really the "result" of the actual pressure between tire and road surface.

Best pressure for max tread life is whatever allows the tire tread to wear evenly across the width of the tire.

Too low, you wear out the outer tread. Too high, you wear out the center tread.

Every tire/wheel/suspension combination will require a different pressure. FWIW, i run 36f/33r on my OEM sized tires/wheels. Simply monitor how the tread is wearing at each tire rotation and adjust pressures and necessary. You do rotate your tires regularly right? Right? ;)

There's an old-school racing guy here in my office. We were discussing tire pressures the other day and he had figured out that 27psi was correct for his car and tires - as soon as he put the tires on - based on some old-timer method that seems to have been lost to us young guys. He was concerned because the door jamb was recommending 30psi. I didn't find out what his method was. :lol:

There's an old-school racing guy here in my office. We were discussing tire pressures the other day and he had figured out that 27psi was correct for his car and tires - as soon as he put the tires on - based on some old-timer method that seems to have been lost to us young guys. He was concerned because the door jamb was recommending 30psi. I didn't find out what his method was. :lol:

Please ask him what this old timer method is. I'd like to hear this.

Don't forget to compensate between front and back for the rolling circumference. You use the chalk test you do in the parking lot to make sure all 4 tires have the same circumference (loaded) and saves your AWD system from fighting itself. I can't remember if that is in my owner's guide or not.

I have gotten 1 or 2 better MPG making sure the air pressure in my wagon is good - and it seems to coast better.

Every tire/wheel combination is different - it does take some experimentation to make sure you have the right pressure. Max treadlife is achieved as mentioned above - a good alignment, proper pressure, and minimal abuse.

I ran the shoulders off of the RE92s my wagon came with in 14k miles, when the car was new. I am much nicer now, but the car would just not break loose unless I really turned hard.... :-)

Bill in SD

All I was really saying was - why would one buy a tire with a 200 rating if one was concerned that much with wear?

Just trying to squeeze in as many autox days as possible. :D

I play with the pressure at the track, then adjust afterwards. 225/45/17 Kuhmo MXs with -1.5f, -1.2r, 0.0 toe. Typically i set it in the 40s street, but am wondering now if I should go lower.