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Discussion Starter #1 (Edited)
I purchased this 08 in March. Ive recently started looking for a winter tire/wheel package. During this process I have found the following issue.

Issue: My X3 has the 19" package which looks to be from the factory as follows:

FRONT: 19*8.5 46mm offset Tire: 235/45-19
Rear: 19*9 51mm offset Tire: 255/40/19

MINE HAS 255/40/19s all the way around!!! Should this be of concern to me??

I have not noticed any ill effects in the past 14k miles that I have put on the vehicle since March, but I hate finding things like this, that make me worry.....

Thanks!
 

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A more practical setup - no downsides that I can think of.

The wear rate on those 40 series tires will not be too good, but at least they will wear at close to the same rate.
With the original staggered setup, the rears would wear much quicker than the fronts,
but they would have to all be replaced at the same time anyway.

I'm kind of surprised that 255's fit on the front with no issues.
But 14K miles with no evidence of rubbing should be good enough.
(I think that the rear can run as wide as 275's.)
If the handling and steering response feels good to you, no cause for concern.

The 1/2" narrower rim width in the front is probably the min. spec. for 255 wide tires,
but the upside is it gives you more rim protection against curbs.

Allows you to do tire rotation if you want.
 

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Given that IIRC BMW advises against rotation and the fact that the wheels are still staggered (albeit only a bit), I would think tire rotation might not be a great idea.

I'm kind of surprised that 255's fit on the front with no issues.
But 14K miles with no evidence of rubbing should be good enough.
(I think that the rear can run as wide as 275's.)
If the handling and steering response feels good to you, no cause for concern.

The 1/2" narrower rim width in the front is probably the min. spec. for 255 wide tires,
but the upside is it gives you more rim protection against curbs.

Allows you to do tire rotation if you want.
 

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Larry, I guess what Supercourse had on his mind was just to switch wheels on the same side, not the rotation itself.
 

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Larry, I guess what Supercourse had on his mind was just to switch wheels on the same side, not the rotation itself.
Not if they are directional tires - which they probably are being 40 and 45 series performance tires.

I did have a regular F to R rotation in mind as the tires (if not the rims) are all the same width.

The increased neg. offset on the 9" rims could effectively put the center of the tire contact patch in more or less the right spot when on the front.
That is, the steering and suspension is set up for a 8" or 8.5" wide rim, so you don't want to spread the extra width of a 9" quite equally.
The 51 offset moves that wider wheel just less than 1/4" inboard.
What about the 8.5" wide rim on the rear instead of the 9"?
Don't know for sure, but with no steering geometry involved I would think that it works out.

Point was that with tires all the same size, rotation should be possible, whereas with a factory staggered setup it's just not on.

Not suggesting that I would necessarily do it if in the OP's position, but at least it can be considered.

As I see it, BMW's position is that for their cars in general, they don't think the upside of rotation outweighs the downside.
No evidence that rotation makes tires last longer, just helps to ensure that all 4 need replacing at the same time.
The downside is that after a rotation handling suffers while established wear patterns are being overcome in the new position.
From BMW's point of view, handling should trump tire replacement cost or convenience of the car owner.

xDrive tends to even tire wear out compared to the RWD models, but not entirely of course.
And BMW's characteristic negative rear camber is always a factor.
In Europe as I understand it, costly tire replacements are accepted as part of the price of admission (RFT excepted).
X3 owners with standard tire/wheel configurations should be happy that they can get over 50K miles out of a set,
without even pondering the to rotate or not rotate conundrum.
 

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Discussion Starter #7
No Rotation planned... I was more worried about the larger overall diameter of the front due to being on a more narrow wheel having some negative affect on the X-Drive system.

There is no rub what so ever in the front....

Thanks for the input!
 
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