03 boxster tire wear

[dkriebel]

I'm buying a 03 boxster s with 9000mi. Rear tires are wearing slightly uneven on the inside. Is this normal? What is causing this? How can I fix it? Is it wise to knock tires off rims and switch sides? Thanks

[larez2]

They should wear unevenly if they are are aligned properly.

http://www.986faq.com/2-0/default.asp:

"The Boxster has negative camber on its wheels. This means that the tops of the wheels slant in toward the middle of the car. This negative camber will result in more wear on the inside edges of your tires than on the outside."

I wouldn't rotate them, but that's just me.

HTH,
Larez

[deliriousga]

Like larez2 said, they should wear unevenly. Look at the back of a Boxster the next time you see one on the road and you'll see the camber is negative enough it's very noticeable.

I wouldn't pop the tires off and swap rims to rotate because then the negative camber will take your angled tire and it will be putting undue pressure on the edge that's thicker and now on the inside.

I started using bi-directional performance tires on the rear so they can be rotated without coming off the rims. Then the angle when they are rotated is correct. This helps me keep from having cupped tires and the road noise that comes with them. Combined with uni-directional tires on front, it gives me the performance I want and the 25-30K miles I like from a set of tires.

Get your tires balanced often (3K-5K miles max) since they can't go front to back. A cheap way to avoid excessive road noise and premature wear.

[lexuspilot]

deliriousga,

What tires do you have on the rear?

[deliriousga]

Originally Posted by lexuspilot

deliriousga,

What tires do you have on the rear?

Kumho Ecsta ASX. They're "W" rated (168mph I believe) AA traction, A temp, 410 wear ratings.

[larez2]

25-30k miles per a set of tires, damn that's gotta be a record or something for a Boxster. I thought about 15k was the absolute top for a set, lots of dudes only get around 10k per a set. I guess it ultimately depends on the tire brand and how you drive.

deliriousga, how do you like your Kumho's? I am due for a new set of tires pretty soon here - I have P-pezros now, but I was actually looking at the Kumho's the other day.

Larez

[clubhead]

Originally Posted by deliriousga

...I started using bi-directional performance tires on the rear so they can be rotated without coming off the rims. ...

Honestly, I don't even bother rotating the tires. Someone correct me if I'm wrong but I reckon bidirectional tires does not grip as well in the wet compared to directional ones.

The rubber on most tires will lose most of its effectiveness after about 2 years on the road, irregardless of the amount of thread left. Rubber ages. I've seen some cars which has been garaged with very little mileage on them. The tires may look brand new but if you try pressing the rubber on those cars compared to brand new tires, you can tell that they have 'hardened' over time.

I change my tires after 2 years even if there's decent amount of thread left. Just take the car for a track day before changing them to 'maximise' the returns

If I'm driving some Jap sedan, I would bother to rotate since grip and handling is not what I'm after if I drive those cars. On a Porsche, I think it's considered a sacrilege to rotate tires Especially so if you can afford to spend on a Porshce but want to save a couple of hundred on tires... no offence people.

[dkriebel]

man you guys are good thanks for quick, great answers!

[Brucelee]

I would like to see the rear tires on ANY boxster or 911 after 25K miles. Color me skeptical.

[deliriousga]

Originally Posted by Brucelee

I would like to see the rear tires on ANY boxster or 911 after 25K miles. Color me skeptical.

Aaahhh, you must remember....it's my wife's car. It is only driven like a Porsche two days a week if I'm lucky.

I put the first set of Ecsta ASX on the rear at 30K miles, the next set was just put on at 61K miles.

[RandallNeighbour]

I'd have to say I disagree with you all who say not to knock off the rubber and put it on the other side (unidirectional tire "rotating"). The way to make it work is to have it done every 3k or so when you have your tires balanced. Costs a little more, but the tires will wear evenly then and I've noticed it's kept my Kumho Ecsta MX's from becoming noisy.

I have 11k on my first set of tires since I bought the car and they're wearing quite evenly on the back. Now the front is a different story because I have some cupping already and that can't be avoided with the kind of "rotating" I'm suggesting.

Disclaimer: If you do it when you see inside wear (or 5~8k), it's too late and I'd have to agree that doing it will only make the tire wear quickly and cause an unsafe driving situation.

[Adam]

I have 13k mi and 2 yrs on my pilot sports and they still look real good. Even tire wear accross the board and decent tread depth even with about 25 auto-x runs on them. I'm sold on the michelins and the next set will definately be PS2's.

[TOM986]

I got 22,000 on my first set of Michelins and they wore very evenly. The fronts were still good for a while, but I changed them because I went to a different brand of tire.