What causes a tire to wear in the center besides too much air? I'm running 225/40/18 Bridgestone S-03s on a 18x8.5 wheel with 31psi in the rear tires. It seems tire pressure is more inportant with lower profile tires. I didn't think 31psi would be too much but i'm learning it might be. I'm going to put 28psi in them and see what happends. As it is now i'm running in the wear marks in the center of the tire and have plenty of tread on the inside and outside. If someone could explain to me what might be going on that would help.

 

You're driving too slowly around the corners.

 

Here is a pic of the tire. It's kinda hard to see the wear with the dirt on the tread but the center is almost slick.

 

rims might be too wide for the 225's.....causing them to bow out in the middle

 

Don't let the 225 S-03s fool you, they are wide. My contact patch is 9in, i'm not sure of the overall width though. I know the rims aren't too wide for the tire.

 

The tires are plenty wide for the 8.5in wide wheels. They are as wide as 245 Kumho Ecsta 712's. I think it's the tire pressure. I only noticed it after a 1800 mile road trip to Florida and back. I'm going to let some air out and try 28psi.

 

I just put 28psi in them and took it for a spin. They grip so much better off the line now. I guess a few more miles will tell if it helps with the tire wear.

 

Note that the wear bar to the left doesn't have that much left on it either although the center one is certainly past. Yes the center wore more quickly but I don't really think drastically so. Of note is that the outer tread block edge is not worn much so they have not see an lot of cornering sideloads that would wear them quicker. Have these tires ever been rotated (like my BMW OE tires, they might not be rotatable due to different sizes front and rear)? If they had, you would have probably seen more even wear as the front will wear the outer shoulder more than the rears from turning. Just a thought.

Edit: rereading the first post I see that it is a rear tire (which had had guessed by lack of outer edge wear). The rear only P7000s that just came off my M3 look pretty similar with more in the center and less on the edge but I think this is more nature of the beast than a specific example of an air pressure or otehr problem.

 

I'm running 18x8.5 on all 4 corners so rotation is not a problem. I may rotate them tomorrow if i have time. I'm a little affraid to put the rear tires in the front due to them being almost slick in the center. Is there any more danger in having them in the front then in the back?

Here is a better pic

 

Pretty much once you are at the wear bars or past, it is too late. The idea for rotation is to spread the wear during their functional life out farther but you are already past that. Generally on a RWD car you will want your better tires on the rear but that is under the assumption that you have decent tread remaining to go to the front. These will be risking hydroplaning and steering loss if you hit much water.

Salute these tires for a job well done and move on to the next set and rotate them each time you change your oil. If nothing else, that means you will be looking at them every 3000-5000 miles and you can catch and correct any trends then isntead of suddenly looking up 15000-20000 miles later and seeing wipted out tires that are too late to be helped.

 

I bought the car 4 moths ago and drove it 800 miles back home. I looked at the tires when i got back and they didn't look bad so i said i'd rotate them when i change my oil. Well I changed my oil late and by the time i was done it was too dark to rotate the tires. Well i forgot about it the next day and in a week i was off to florida 1800 miles later they looked like the pics above.

I'm going to order 2 new S-03s next week. My front tires have the mormal inside wear but still have plently of life left in them. I'll drive my Hatch when it rains and my m3 when it's dry untill i get the tires changed.

 

Try a different tire pressure gage if you haven't yet.

I just about thought I was going insane once until I fgured out my gage was just reading wrong.

 

check your alignment - chances are your toe is off.

from 12/03 GRM:

"consider that if the toe setting is just 1/16th (0.06 degrees) off its appropriate setting, each tire on that axle will scrub almost seven feet sideways for every 100 miles of driving."

after reading this dear john section on alignments, i went out and eyeballed my rear wheels, which have azenis on them that are bald like a slick in the middle third, yet about 50% on the outer edges. sure enough, major positive toe on both sides of the rear, which never was professionally aligned after a rear disk/trailing arm swap.

i don't have any experience with your particular tire, but this seems to be the norm for this condition on any tire, with the only exception being over inflation, which was already mentioned.

hth.

(same thing happened to my wife's car last year, and i never understood why...)

 

Let me mention this. While on my trip i stoped at a rest stop and check the tires and saw there were for the lack of better words "rubber shavings" on the tires. It kinda looked like the rubber that's left from using a pencil eraser. This was after 6 hours of driving at 80mph.

 

As suggested above, wear in the middle of the tire is usually indicative of very pressure causing the middle to bow out, or lots of static toe and highway driving. From my experience, narrow rims relative to the tires will cause the center to bow out, but center wear from this is probably secondary to poor pressure/alignment.

 

What's the recommended air pressure for your car?

I can't remember where I heard this, but I think it was from a person who works for a tire company. He said that too low of a pressure will wear out the center of the tires. That's contrary to what we would think, but he said that low profile tires depend on air pressure on the sidewalls to flatten the tread or else the center of the tread will be bowed out.

Check your recommended air pressure and if you're running the right pressure, then I'd get the alignment checked.

I run 40psi on my S03's on my Audi and I get a little more wear on the shoulders. I believe the recommended air pressure is 36psi, so I doubt you're running too high a pressure.