Just replaced my factory installed original Michelin Pilot 4S tires, approx 17,000 miles of what most would consider, gentle use. Plenty of tread however, after picking up a small screw in the outer most edge of right rear tire, I just went ahead and placed an order for replacement of all 4. The photos clearly show extreme wear and cracking on inner edge, any recommendations on how to avoid such going forward or if this is typical at this mileage level?

 

if these are the rears with 17k miles this is pretty normal as the cars have some negative camber and this is how they wear. I run the same tires and I am lucky to get about 12-15k miles.

 

alignment

 

I have to pay double to get my tires to last to 10k miles (I’m on my 3rd set of tires at 12.5k miles).

Those tires look amazing to me for 17k miles.

As others have said, alignment is the likely culprit and the wear is to be expected.

Here’s one of my old tires for contrast.(understanding it’s a front outside, not rear inside… just illustrating how good 17k miles would seem for some people)

 

There is no reason for tires to wear like that. If you are not tracking the car exclusively then get a proper alignment with less negative camber. Mine came with excessive negative camber on the rears and I had it aligned when I got new tires. They are wearing evenly now.

 

This is not from negative camber. Could be a toe issue.

As stated, get your alignment checked but at 17k miles you cant complain too much

 

New 991s were delivered with P Zeros. Michelin Pilot 4S are the replacements to get. Be sure to have a proper realignment at a shop with the latest Hunter rack. Done right handling, ride and longevity are obvious. 17 k miles is not too bad by the way. In my experience PS4s seem to wear faster after they age beyond 4 years or so.

 

Any suspension mods on your car?

 

No suspension mods whatsoever

 

As stated wear is outside of a normal pattern, wear so far on the outside is not the factory camber. Your wear is pretty much on the sidewall, I'm not a tire expert but if I had to guess that is rear toe out combined with low pressure running or excess camber.

 

cold tire pressure is always set at 32 Front / 36 Rear

 

Toe is off.

 

+1 for toe issues. Camber doesn't cause wear, toe does.

 

yup. thats a toe alignment issue.

 

Pretty common wear pattern on the 991's unfortunately. You can confirm this by searching "tire wear" in this forum.

My first set went at around 10K of mixed driving. Had the dealer (one I trust) check the alignment as I didn't have that aggressive wear even on my 991RS. It was slightly off and they reset to midrange of factory recommended. 9k miles later, same thing. You could align to under factory spec but you're likely going to surrender some performance. Guessing your car has RWS?