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The tread on the rear tires is worn completely on the inside - while the outsides are just past the tread indicator. Michelin Pilot Sports - dealer installed.

Is this normal? Is it the alignment?

It is a CPO but the original owner installed lowering springs (Techart) and upgraded sway bars/links. Also, the tires are 265-35-18 vs OEM 265-40-18, Up front they are 225-40-18 vs OEM 235-40-18, with good tread remaining there.

I am thinking of changing the rears with same tires for now ($650 + installation).

Is it possible to redo alignment on rear axle to more evenly wear inside-to-outside?

Any comments and suggestions? Thanks ... .
 

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You could have the tires swapped after 4,000 miles or so. That would even out the wear some and make the whole tire usable.
 

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Sounds like a bad setup without proper alignment. Stock shocks etc have only so much adjustability but a proper alignment can help even with stocks. i'll bet if you look at the tires from the rear that the outside edge barely touches the ground.
 

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What PSI do you run the front & rear tires?
 

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I would have a complete alignment before replacing tires. Lowering may have produced excessive negative camber for street driving, or perhaps toe settings are out of spec.

I wonder why someone switched tire sizes front and rear. Front and rear tire diameters are now about equal, whereas the rears are about .9" taller using OEM sizes. That probably didn't contribute to the excessive tire wear, however.
 

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Discussion Starter #7
32 front & 37 rear. But I have to admit that keeping them there takes frequent checking. And I have slacked some there - maybe every 1-2 months.
 

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The suggestion to swap tires would not be effective (R to L, L to R) as the tires on both sides have worn in the same fashion. And you cannot turn the tires, inside to outside, as they are asymetric design. Pay attention to what Jim Michaels said, even though he says things very quietly.
 

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The tread on the rear tires is worn completely on the inside - while the outsides are just past the tread indicator. Michelin Pilot Sports - dealer installed.

Is this normal? Is it the alignment?

It is a CPO but the original owner installed lowering springs (Techart) and upgraded sway bars/links. Also, the tires are 265-35-18 vs OEM 265-40-18, Up front they are 225-40-18 vs OEM 235-40-18, with good tread remaining there.

I am thinking of changing the rears with same tires for now ($650 + installation).

Is it possible to redo alignment on rear axle to more evenly wear inside-to-outside?

Any comments and suggestions? Thanks ... .
I would have a complete alignment before replacing tires. Lowering may have produced excessive negative camber for street driving, or perhaps toe settings are out of spec.

I wonder why someone switched tire sizes front and rear. Front and rear tire diameters are now about equal, whereas the rears are about .9" taller using OEM sizes. That probably didn't contribute to the excessive tire wear, however.
I agree with Jim - First it seems odd that they would install the PS2s, but make them the wrong size - so close, yet so far away... I would guess the previous owner had the car lowered, but then did not get an alignment, or that alignment wasn't very well done... or, it got knocked out of alignment. Or, some of all three. Either way, either the toe is out by a mile or the camber is way too much for street driving, maybe both.

You should not only replace the rear tires, but also replace the fronts with 235/40s, otherwise the car will push a lot. Once the tires are on it, get a good 4-wheel alignment. Bite the bullet now, and the car will handle much better.

brad
 

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Ditto for what Beez said. Sounds like way too much negative camber in the rear. Also, get the correct size tires for proper handling.
 

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Swap all 4, I suggest you change to Bridgestone Potenza RE-11's. handling as good or better than PS2's and cheaper. They look better too...
 

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I basically agree with all of the above. The problem is almost certainly alignment - simple as that. Being cost conscious, I would probably live with the front tires 'til they are gone - but if money is less of an object then replacing all four is better.
 

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Discussion Starter #13
Thanks for the recommendations. This is a great forum!

My plan is to replace the rears for now with same size/type tires - and fix the alignment as best possible. Next time, hopefully in 12K+ miles, I will upgrade to 19" wheels with properly sized tires.

If I had budget to throw around I would do the 19" upgrade now. A year from now both my sons should be out of college. Hey, maybe then I could just trade up to an '09 with 19" wheels!
 

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Hi pbxtr,
You're welcome and welcome aboard.
I would recommend going to the OEM size when you replace your rears. Based on the sizes you quote above, assuming my quick math is correct, your fronts are 8mm total shorter in overall height than OEM - meanwhile, your rears are 26.5mm total shorter in overall height than OEM (over an inch). The PSM and ABS systems don't like too much variance (front-to rear) from stock - I'm told 3% is the limit - so I'm kinda surprised your PSM or ABS hasn't acted up. I would get it aligned with the old tires. And, just for interest, please ask for the "as-found" numbers as well; it will be of interest to some of us geeks, and it almost certainly will all make sense in hindsight. Good luck.
 
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