I have a 2009 C4S with PS2 and 7500 miles. The outside edge of front and rears are worn on 3-4 inches nearest the outside. The rest of the tire is in great shape. I realize that I need new tires and I have reasonable expectations about the life of these tires on a Porsche but is this normal? Do I need to do something before I put new shoes on the car? I read that the inside wears on these cars so I'm a little confused. No track time on the car and nothing that I would have done to promote such a wear. I have also noticed that the car drifts/slides in a hard turn. The other C4s's I test drove seemed to suck to the road.

Any comments and suggestions would be helpful.

 

if you haven't been runiing them over inflated it could be a toe issue...not unusual to wear out the rears with that mileage but usually the fronts last for two sets of rears....and like you said it is usually the inside edge that goes due to negative camber...did you change the ride height without an alignment?...get a fresh 4 wheel alignment when you get the new tires and watch the new tires for unusual wear

 

Yep. Most likely an alignment issue. However there's not much you can change with the standard suspension setup (short of GT3 LCA's)

 

I don't believe they are over inflated. Can you suggest a proper inflation for these tires? Since the car is in warranty, should alignment be something that is covered? If not, what is the going price on an alignment?

Thank you

 

there should be a sticker either in one of the door jams or in the gas cap with the proper inflation pressures for your car (also in the owners manual)...you would have to be well into the 40lb area to get that kind of wear and even then from your description of where the wear was taking place it is not likely the problem...these cars don't always come from the factory with a proper alignment (although, when it was serviced you should have been advised about the unusual wear pattern)...I doubt alignment is a warranty issue unless a part has failed...if your car doesn't have adjustable corners then you can't corner balance so an alignment will be all you need...prices vary as does the quality of the alignment...get a recomendation from somone in your area...with a good alignment you will save the cost in tires

 

It is common for PS2's to wear on the outside edge.

I had the problem on my C2S, were as all other tires seemed wear evenly.

Do a google search for "michelin Ps2 outside edge wear" and you will see a lot of results on the topic. I would imagine that Michelin would never admit to an issue, but I would also imagine that the issue will be resolved on the new PSS.