matmanx1

I'm considering a purchase on a 2004 Boxster S Spyder 550 and if I do so it will be my first Porsche. I'm wondering about the typical lifespan of a set of tires, specifically the OEM stuff like the Pilot Sport 2 or P Zero Rosso. And do the front and rear seem to wear evenly or do the fronts seem to need replacing more often than the rear or vice versa?

I'm not planning on taking the car to the track or autocross but will be using it as a daily driver back and forth to work. Thanks!

ep3_lol

Tire life is dependent on the construction and use. Nothing about the Boxster will make it any different from any other car out there, except for the inability to rotate back to front. You can buy a harder, high mileage tire that will last many tens of thousands of miles if you like, so long as it comes in the right size. You don't need the OEM tire just because it's OEM. If resale value is a concern, then just replace what you get with the OEM ones before you sell; no one will know the difference, because there won't be one.

VGM911

If I recall correctly, Porsche recommends replacing tires once they're six years old (regardless of tread wear).

matmanx1

I know Porsche recommends sticking with the N rated rubber. Do you mean going with a non N rated tire? And if so, would I be severely hampering the handling attributes of my car? I've owned vehicles with high performance tires before and I think I typically got around 20k miles out of them. Could I expect a similar lifespan out of an N rated set?

ep3_lol

The letter ratings deal with the top speed the tire is rated to handle. N is fairly low at 87mph. If you are sure you won't ever top this speed, then yes they'll be fine. Here's some good info on that topic. Grip will be significantly reduced with a higher mileage tire, that is the nature of tire mechanics. The more grip a tire provides, the quicker it will wear. Less grip is of course detrimental to handling, but you won't notice if you're just driving back and forth to work. Noise however may increase, I'm not sure how tread design and compound affect that.

I don't have any hard numbers for you though. The mileage will generally be advertised with the tire and you can be reasonably sure that they will last that long so long as you keep them inflated properly. I have a spirited driving style, so tire life is just a casualty I accept, and I don't pay attention to how long they last me; I just make sure they're wearing properly and are in good shape.

Macster

Based on my experience with my 02 Boxster (driving it over 258K miles) running any of the N-rated tires -- my direct experience is with Pirelli and Michelin but based on what others have reported with other brands all tires are about the same in this regard -- with a proper alignment -- and assuming you avoid bumping into things in the meantime that can knock the alignment off -- you should get 15K miles or more (I've managed over 20K without much trouble) from the rear tires and twice that from the front tires.

However, if you like to nail the gas pedal around corners rear tire life can be shortened by around half. Also, the right rear tire will wear much faster than the left rear tire.

Sincerely,

Macster.

500

258K miles? Wow, good for you Macster!

Do you know why the right rear wears so much more?

Macster

My info is the right rear tire can wear faster than the left rear -- at least in USA cars and ignoring uneven tire wear arising from abnormal alignment -- due to the lack of a LSD.

The diff in the Boxster is a simple diff and during a turn in order for the outside wheel to turn faster torque is transferred to the inside wheel. Since this wheel/tire is not loaded as much as the outside it can spin.

Depending upon how aggressive a driver is with his car's throttle and cornering speed the right rear tire can experience negligible wear -- to the point that after say 20K miles the two rear tires are nearly indistinguishable from each other -- to the point the right rear tire is down to its wear bars thousands of miles ahead of the left rear.

The right rear tire wears more since in the USA most turns are to the right and are made while at a slower speed made under conditions that can lead to slippage of the right rear tire more often then the left rear.

Sincerely,

Macster.

500

Ah, nice explanation, I understand now. Thank you!

ep3_lol

I've got about 20k miles on my set Continental ExtremeContact DWSs and they are very, very far from the wear bars. Both back and front.

Macster

IIRC those are not N-rated tires and I have no tire life experience with non N-rated tires.

But good tire life can be had with N-rated tires.

I mentioned my Boxster in an earlier post.

But that is not the only Porsche with which I have experienced good tire life.

Recently my Turbo had a flat left rear tire --- the culprit: A small screw way over nearly to the edge of the tread face/sidewall border -- and the tire was deemed unrepairable. Check that: In fact it was repaired but failed to hold air and I was advised to replace it. That the tech wasn't kidding was made obvious when the tire went flat in just hours after the repair attempt.

Might add this tech has fixed other flat tires for me and this is the first one that didn't take. I was told that the tire had suffered some sidewall damage either from running too low on air pressure or from the screw making contact with the sidewall inside the tire.

Anyhow, at the dealer to get new tires and I learned I had bought road hazard coverage when the current tires were installed.

To qualify for replacement the flat tire needed some tread life left.

The tech measured the tread remaining -- across the tread face -- and it was 3mm. The limit for replacement was 2mm. So the tire had 1mm over the lower limit and the flat tire was replaced free of any cost to me. Since the tires had so much wear though of course I had to replace the other tire at my expense.

But I got almost all my money out the tires. The miles on the tires? Around 23K miles.

The tire brand? Bridgestone. But Continental tires have delivered similar longevity on my Turbo.

Sincerely,

Macster.

mikefocke

N rating is a Porsche specific rating and is the result of specific tire tests conducted by Porsche and approval to their standards. It has nothing to do with speed rating letters though presumably Porsche isn't going to OK a tire whose construction makes it unsafe at the speeds that Porsches sometimes attain. And the number after the N is just the next in a series, N3 is not necessarily better than N0.

Tire life can be helped or hurt by an alignment which favors even tire wear over extreme limit handling. After a professional alignment by a mechanic experienced in setting up Porsches for racing, I put a set of PS2s on and only took them off 6 years and 16k later because of age concerns. When removed, the rears (which on most Porsches wear perhaps twice as fast as the fronts) had about 1/2 tread left and the fronts 2/3. I didn't slide around corners but I did take 90 degree corners at 45MPH with some regularity.

While I love Michelins and used them exclusively when I replaced tires (and have for about 30 years on probably 40 cars), there are many others who swear by specific tire models and brands which are cheaper.

VGM911

+1

And, I think all of the Porsche recommended summer tires are Z-rated.

ep3_lol

I didn't know they did this. I thought 87 seemed awfully low for a Porsche tire. I know I'd be dead if the tires on my car could only handle that

matmanx1

Thanks all. Very informative!