Quote Originally Posted by JohnL View Post
One drive wheel? Get your differential fixed!

An argument can be made that rotating tyres actually increases overall tyre wear. It goes like this; As a new tyre wears when fitted to a particular corner of the car, it wears according to the particular characteristics of the suspension on that corner. This includes static camber angle and the degree to which that suspenion gains camber with suspension defelection. When new the tyre's tread will not match the characteristics of the wear that will occur on the suspension to which it's fitted, it will have areas where the contact patch loading is more heavily loaded and areas where less heavily loaded (typically more loaded on the inner part of the contact patch due to neg camber).

The new tyre will be 'flat' across the tread, but is likely to wear more on one side of the tread than the other according to static and dynamic camber angles seen in service. When new the contact patch will be more heavily loaded on one side than the other, and will tend to wear more on the more heavily loaded side.

As it wears in to the suspension this difference in loading in different areas of the contact patch will even out as rubber wears away until the loading is more equal across the contact patch, but the tyre will go through an initial period of 'accelerated' wear until this state is acheived.

If we now move that 'worn in' tyre to a different corner with a different suspension characteristic it will go through another period of 'wearing in' where the wear rate in some part of the tread will be faster than it will be once the tyre has worn in to the characteristics of the 'new' suspension.

So, when we rotate tyres we may spread the totality of wear more evenly over all of the four tyres, but each individual tyre will tend to wear more quickly. This may not be a big difference, but in principle it exists.
A non LSD FWD or RWD (unless you are a grandma driver) will always wear out the drive wheel quicker than the other, whereas, an LSD equipped vehicle wears far more evenly!! Burnouts cause this problem even worse!!

I understand what you are saying about the camber wear, but if you have a correct suspension/camber setup and correct PSI in ur tyres for your driving style, then the camber wear should not generally be noticeable (I had 1.5 degree to the negative on the back of my EG and 1.75 to the negative on the front, and the tyre wear was even across the tread) so though this is a factor, i would be more concerned with uneven wear front:rear.