Then maybe you need to abandon Porsche specs....

I drive with other Porsche pals on weekends so much I checked my tires over the weekend right before I went out and saw this! Down to the chords on my inner rears. Scary actually and I’m glad I checked. New tires ordered and I clicked on the banner for Tirerack on this forum so hopefully Pedro’s site gets some sort of credit. Easy to do, as it brings you right to the Tirerack site to order. Do it next time you order. Happy Porschering!

It will be good to keep you around for a while longer.

In addition to the new tires,, I might suggest getting the suspension/alignment checked. That is a lot of wear on the extreme inside of the tire. That looks a little unusual. The wear could be made more even.
I do wonder if that kind of wear indicates you are not getting the best contact patch for the kind of driving you do.

Bottom line, it is relatively no so expensive and could make a significant difference.

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JM-Stamford,CT
It will be good to keep you around for a while longer.

In addition to the new tires,, I might suggest getting the suspension/alignment checked. That is a lot of wear on the extreme inside of the tire. That looks a little unusual. The wear could be made more even.
I do wonder if that kind of wear indicates you are not getting the best contact patch for the kind of driving you do.

Bottom line, it is relatively no so expensive and could make a significant difference.

Thanks JM. I had an alignment done at the dealer 3 yrs ago when I had them replace the fronts and so maybe it’s just time. I know the 911 does wear the inside part of the tire faster, especially with the weight back there. My weekend group drives do get a little spirited, so I’m glad I saw it in time.

I had a similar conversation on another board. On my NSX I only had 4000 miles on the tires, but I checked and here the rears were worn out. Turns out they get a 100 foot skid pad result of 1 g by giving the rears a 1 degree inner bias. Check your alignment. That was years ago. I am back in Porsche land now.



Edited 1 time(s). Last edit at 09/08/2021 10:36AM by Rev Dennis. (view changes)

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Rev Dennis
I had a similar conversation on another board. On my NSX I only had 4000 miles on the tires, but I checked and here the rears were worn out. Turns out they get a 100 foot skid pad result of 1 g by giving the rears a 1 degree inner bias. Check your alignment. That was years ago. I am back in Porsche land now.

Thanks, well these rears had about 15K on em till it got to this point, and I think that’s normal for my car, so I think it’s ok given my style of driving (I put 10k of those miles on them), but I’ll check it out.

I agree.

I suspect that someone wanted an aggressive suspension setup. If you made the rear more neutral, you will probably get better wear.
To be clear, 15K is very short in the absence of track or other aggressive abuse.

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JM-Stamford,CT
I agree.

I suspect that someone wanted an aggressive suspension setup. If you made the rear more neutral, you will probably get better wear.
To be clear, 15K is very short in the absence of track or other aggressive abuse.

That shouldn’t be the case, as I had the 4 wheel alignment done according to Porsche specs at a Porsche dealer 3 yrs ago. It is not unheard of to get only 12 -15k miles on rears in a 911. Plus, my tires are the Bridgestone N1 rated tires which have a very short tread wear rating in comparison to its peers.



Edited 2 time(s). Last edit at 09/09/2021 01:28PM by CarreraLicious. (view changes)

If that is the result of "Porsche specs" then you should consider your options. Perhaps you should affirmatively ask for a more neutral setup to preserve your tires. You might consider a more balanced set of tire parameters too. All seasons are just fine for us. In fact, I would argue they are much better for us 9 months out of the year. Further, you should not assume the dealer set up the car correctly for you. There is a range of "specs" that I have seen on many cars. All of which are "acceptable" but some might not bee "appropriate." So what "specs" did they use? They might have just carried over the specs from the guy before you who insisted on a super aggressive track stance. Alternatively, they might have left an adjustment bolt unsecured. They might have simply done it wrong. Perhaps trust but verify is the order of the day. Just sayin'

Also, the fact that "it is not unheard of" for tires to wear like that is not a valid argument. It is not unheard of to get only 30,000 miles out of a clutch. But If one does not abuse the clutch, that is absurd.
It is not unheard of for the Porsche engines to burn 2 qts of oil in 1,200 miles. But that burn rate will do collateral damage and in my view, that is woefully unacceptable. In either of those events, I would be looking to change or repair something to cure or remediate the problem. I submit you should consider the same with respect to your tire wear.

Bottom line, there are ways to minimize the kids of wear you are seeing. You are not a track guy, you are not an autocross guy, boy-racer or even a long distance driver. You should be at the conservative end of the wear spectrum not the bleeding edge.
That kind of tire wear at the mileage you stated, and without other abusive conduct, should not be acceptable and further investigation is absolutely warranted.

Various threads I’ve read in 997 forums indicate the negative camber on this car causes this inner tread wear on the rears and many get between 12-15k miles out of them. I’m actually ok with that, and I don’t want all seasons on my sports car, but YMMV. I will get it checked out though.

997 tire wear:
[rennlist.com]

are given as a range and it is up to the owner and the mechanic to figure out where within the spec they want to set the car up.

I had a wear problem and visited a mechanic who set up cars for the track so he knew the effect various settings (still within the Porsche specified range) would have. I told him these were new wheels and tires (actually take offs from a new car with 13 miles on them which were cheaper than buying new tires). I told him the problem and what kind of driving (moderate, no track, wear biased) I wanted and he set it up that way. I eventually retired the tires for age reasons, not wear and never had a complaint.

Experience of who does the alignment matters. So does communications.

Mike said it better than me. What he said, was the point I was trying to convey.