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Incredible tyre wear and possible geo/setup problem

GD

Barcelona
Joined
20 Jun 2007
Messages
1,280
Hi,

Would like your advice on this. A friend of mine has a (non-911), which is eating through tyres like you wouldn't believe....so hoping it's still relevant to this forum!

The symptoms are completely even wear across the rear tyre, but it goes from brand new to on the legal limit in no more than 4,500 miles.

Since this has happened to 3 rear tyres in a row, he's been driving it very cautiously, not wheel spinning, careful acceleration from the lights, no big one round the roundabout and no track days.

It has the engine at the front, so the rear tyres don't have a weight on them like the 996 (but it is rear wheel drive).

They are Pirelli tyres, which are OEM specification. The manufacturer claims you should get between 15-20k miles under normal driving.

They are suggested a geo set up....but I'm wondering if this is really the cause. Surely a geo would only be appropriate if you are getting uneven tyre wear. This is litterally like someone has just been simply wheel spinning the wheels off the lights (which is not the case).

The car is an 04, with 30k miles.

Does anyone agree that a geo is required, eve if the wear is completely even?

PS The fronts are still like new and have covered about 10k miles now.
PPS The car is a Nissan 350Z
 
Not quite clear from your post if this is affecting just one tyre, or is it across both rears?
 
Hi,

Thanks for the quick reply. It affects both tyres, completely evenly. Both were replaced at the same time and both wear out at the same time (now both at legal limit).
 
Towing a caravan?? :p

TB
 
On my old 996 Targa with Pirelli's I only got 4000 miles out of a set of rear tyres. If I were him I would change all 4 tyres for a different make (Michelin?) and see what happens.
 
I remember this being an issue on the Honda NSX. Apparently with the OEM set up, the car would get through a set of rears in less than 10k miles. However with the toe-in/ toe-out minutely adjusted, they could be set to last a lot longer than just 10k miles. I think this all points to a geo as you suggested in your initial post.

~ Maxie
 
Maxie think you could be right

http://www.familycar.com/Alignment.htm

"The toe measurement is the difference in the distance between the front of the tires and the back of the tires. It is measured in fractions of an inch in the US and is usually set close to zero which means that the wheels are parallel with each other. Toe-in means that the fronts of the tires are closer to each other than the rears. Toe-out is just the opposite. An incorrect toe-in will cause rapid tire wear to both tires equally. This type of tire wear is called a saw-tooth wear pattern as shown in this illustration"
 

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350Z....
"
The tyres wear unevenly on their outer (check) edge leading to roaring/rumbling/howling noise which gets worse as wear/mileage increases. Some owners have reported associated steering feel changes and even reduced front end grip.


Nissan GB now recognise that this condition can occur and will inspect tyres when the problem is reported. If they find that the problem is affecting a car, they will usually replace the tyres and reset the toe-in settings of the car to avoid the problem recurring.
"
 
I had a 996TT that ate a set of rear tyres every 3000 miles, after the expense of a geo setup it then got ... yep 3000miles on the rears..

Sold the car eventually so never got to the bottom of the issue, next 996TT got 10-12K out of the rears... so more like it

garyw
 
have had 3 350z's through the garage where i work and none have managed more than 6k from the rear tyres.

still think a geo should be done annually anyway
 
have had 3 350z's through the garage where i work and none have managed more than 6k from the rear tyres.

still think a geo should be done annually anyway
 
Thanks for all the replies. Honestly, he's been driving it more cautiously than your worst Sunday driver and cannot get more than 5k out of them.

Hopefully the Geo fixes it, because it's rather expensive at £3-400 each time!
 
As it is the rears and they are wearing evenly acroos the width of both tyres, it does not point to rear geometry. Does the car have a limited slip diff? It might be a problem with the differential causing the wear, especially, if he does a lot of turning in cities etc.
Just a thought :food:
Big Bob
 
Big Bob said:
As it is the rears and they are wearing evenly acroos the width of both tyres, it does not point to rear geometry. Does the car have a limited slip diff? It might be a problem with the differential causing the wear, especially, if he does a lot of turning in cities etc.
Just a thought :food:
Big Bob

good point big bob, that would do it
 

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