jim010

Have a 99 C4 and running pirelli Pzero Rosso 285 30 18 in the rear. Bought them at the beginning of last spring and did wheel alignment and put on 15 000 km on them. Was stunned to see that they are almost down to the wear bars today. I did not expect that at all. I drive harder in my Mustang and get 50 000 km out of my tires on that car. Mix of highway and street driving. It is her car, and she drives normal. Doesn't punch it off the lights, doesn't push in corners etc ... the rare burst of spirited driving.

I have searched online to see what the hell is up. Seeing that some say 10 000 miles on the low end and 20 000 miles on the high. I'd like to hear more about this out there. A set of rear tires every spring is not what I expected ...

JohnCA58

Is the wear even all the way across or more toward inside or outside. pictures ?

jim010

a little more worn in the middle. Had the camber straightened out by Porsche at the last alignment after I did my strut mounts. Too dark for pics right now, but they are not worn down on the insides.

mattie_k

Tire pressure.

jim010

oh I know about tire pressure. But its not that much more worn the the rest of the tire. Overall the tires are worn down.

fly4beer

15k km very good for rosso...

JTT

What is the rear toe set at? Mine was eating tires too, largely on inside edge and middle. Added a tick of toe to the rear, and big improvement.

DDzPorsche

[QUOTE=jim010;16716952] It is her car, and she drives normal. Doesn't punch it off the lights, doesn't push in corners etc ... the rare burst of spirited driving.

Who knows what she is doing when you are not around.....

Mike Murphy

Alignment. Do a title search and look for threads where suspect tire wear comes with users posting alignment settings. I have over 15,000 miles and my rears are still good (Michelin AS/3) on a 99c2 cab.

808Bill

Rear engine cars is going to wear faster than a front engine...

jim010

Geezuz ... well this is what I was wondering. Do the Rosso's really not last very long. The fronts still look like new, though, with the car being a C4.

Don't know. The Porsche dealer set it for us after buying the tires. Invoice doesn't say. I just trusted them to know what to do. They did straighten the camber, as I said earlier.


Hah! You never know. The fronts look as good as the day we bought them, though.


As I said earlier, Porsche did the alignment, as I had the front struts replaced at the same time. That was last spring. And yes, I have looked at many threads.


Geezuz, no kidding ...who'd have thought that my wife driving her car like a Camry would wear tires 3 times faster than me in my Mustang ... It was a surprise to me. Maybe we'll go back to the ugly 17 inch rims as tires are cheaper for that size.

TexSquirrel

I have about 17,000 on my Michelin PS4S tires and the rears will likely need replacing in the next 4 or 5k miles.
The fronts look great.

jim010

So that's 27 000 km! Rubber on those Michelins must be harder than the Rossos.

DBJoe996

Dang! I run the Michelin Pilot Sports AS3's front and rear. I keep the tire pressures at the recommended psi for 18 inch wheels, 36 front and 42 rear. Over the years my tires do not wear much, so what I have to do is replace them because they age out...over 5 years. They begin to form small cracks around the sidewalls, probably from UV sunlight. I always detail them when washed and put some UV protectant on the tires. For someone who is wearing out tires, get the alignment checked and make darn sure they know what they are doing, with recorded printed before and after settings.

The tire wear factor is also important. What is the tire wear figure for the Rosso's?

Mike Murphy

Alignment isn’t something that is ‘set correctly,’ it’s a series of adjustments with ranges that have pros and cons for those settings. So you could have 5 identical 911s with different alignment settings that all behave differently, handle differently, and have different tire wear, and all alignment settings could still be ‘correct.’

Often, the factory recommendation for alignment will wear out the rear tires faster than a more conservative setting, so as the settings I have on my car.