Tire change - all four a must?

[och]

I have my 2012 X5 with factory 18" wheels. I bought it brand new and so far have put 23k miles on it. The rear tires still have at least 50% of thread but the front tires are worn out. According to my service history, the tires were never rotated, so as expected the front tires wore out before the rears.

I know that BMW recommends changing all 4 tires in order to have the same overall wheel diameter and avoid damaging the transfer case. But in reality, its such a minor difference that it shouldn't affect the transfer case if I only replaced the front tires, since rears still have plenty of thread?

That being said, my transfer case has been replaced under warranty back in April. It's been slowly acting up since early 2014, and so I don't think it was due to the tires, but due to BMW's lousy quality control.

[mitch808]

Yes all four for most any AWD car

[patents]

Don't mess around with mismatched tire diameters... even due to wear. BMW transfer cases are very sensitive to it. And do not ever put the wrong size tires on. I was shopping at a BMW dealer yesterday and the saleslady said someone just traded in a 2013 X5 with a bad transfer case due to wrong tire sizes. They are sending it to auction.

On my wife's Subaru, she recently had a flat, and I bought a used tire on ebay that was the exact same model tire with tread depth that matched the remaining tires. If your rears have 50% left, I would look online for matched used tires with similar tread wear. Can save some big time money.

[-c-]

Originally Posted by patents

Don't mess around with mismatched tire diameters... even due to wear. BMW transfer cases are very sensitive to it. And do not ever put the wrong size tires on. I was shopping at a BMW dealer yesterday and the saleslady said someone just traded in a 2013 X5 with a bad transfer case due to wrong tire sizes. They are sending it to auction.

On my wife's Subaru, she recently had a flat, and I bought a used tire on ebay that was the exact same model tire with tread depth that matched the remaining tires. If your rears have 50% left, I would look online for matched used tires with similar tread wear. Can save some big time money.

Yep my transfer case took a shit because the past driver let his tires get to low and didn't change all tires letting the clutches wear out.

All 4 must be changed at the same time, in fact because you've let the tread get that low and haven't rotated the tires you have probably already caused unneeded wear on your clutches already.

From my research 2011 and 2012 x5 transfer cases seemed to be the most affected and wore out pre maturely requiring over 4 redesigns before they fixed it.

They are also near impossible to find used. 2012 ATC450 anyway. Their usually snagged up and sold as rebuilds.

The dealer told me that the 2011 and 2012 x5 seem to have the most failures for some reason, in 2013 they changed the case entirely to a completely new design and won't work on earlier models.

[och]

They actually did change my transfer case under warranty a few months ago, I believe back in May with around 21k on the clock. The car was always serviced at the dealership, and I'm surprised they never did a tire rotation. I guess I'll replace all four tires and make sure to get them rotated every so often to avoid any potential damage.

With that being said, is there a certain tolerance that's acceptable when it comes to difference in thread?

[eswimm]

3/32 difference max is what I've been told.

[lknbimmers]

Question...
What if you have the 20" staggered wheels and they can't rotated? The front set of tires will wear faster then the rear.
Do you still recommend replacing all four tires?

Also what are signs of transfer case failure?

[smyles]

...or what if I told you all 4 wheels rotate at different speed whenever you turn?

[och]

^

This is why I really dislike these AWD systems, as they are pretty much useless and only add complexity, weight and maintenance becomes more involved and complicated. Not to mention that they make the car feel like FWD.

[Crazy1323]

You can also have tire rack shave a tire to the desired tread depth to match the others

[jiggz]

Is there any online information/literature on this topic in regards to the E70 X5?

I've been told by 2 different SA's whom I've trusted for over 10 years that the AWD system on the E70 X5 does not require that all 4 tires be of the same tread depth.

I recently replaced my fronts but not the rears as they've got a good amount of tread life left. I never knowingly cut corners on maintenance and was willing to replace all 4, but they insisted it was not necessary in my case.

Not looking to start an argument or elicit 'your SA is a moron' comments - just wondering if there is BMW specific info vs. generic 4WD info.

[och]

Originally Posted by jiggz

Is there any online information/literature on this topic in regards to the E70 X5?

I've been told by 2 different SA's whom I've trusted for over 10 years that the AWD system on the E70 X5 does not require that all 4 tires be of the same tread depth.

I recently replaced my fronts but not the rears as they've got a good amount of tread life left. I never knowingly cut corners on maintenance and was willing to replace all 4, but they insisted it was not necessary in my case.

Not looking to start an argument or elicit 'your SA is a moron' comments - just wondering if there is BMW specific info vs. generic 4WD info.

I'm also surprised that BMW never rotated my tires (the car has been for maintenance/warranty repair/recall work) at the dealership 8 times since I bought it. They also didn't mention anything regarding thread depth difference when they replaced my transfer box under warranty.

[X Driver]

In my opinion it is not necessary to change all 4. If you have 20s with different tyres they are not exactly the same even when they are new. Shouldn't be to much but wear is okay..

[-c-]

Originally Posted by jiggz

Is there any online information/literature on this topic in regards to the E70 X5?

I've been told by 2 different SA's whom I've trusted for over 10 years that the AWD system on the E70 X5 does not require that all 4 tires be of the same tread depth.

I recently replaced my fronts but not the rears as they've got a good amount of tread life left. I never knowingly cut corners on maintenance and was willing to replace all 4, but they insisted it was not necessary in my case.

Not looking to start an argument or elicit 'your SA is a moron' comments - just wondering if there is BMW specific info vs. generic 4WD info.

Well considering my dealer has had several transfer case repairs with tires being the culprits at least that's what they and BMW have come to the conclusion of they stand by their call that the difference in tire size creates stresses on the clutch of the transfer case design that will wear the clutches prematurely and cause a transfer case failure.

Just reciting what they told me. In fact they take a tape measure and measure the circumference of all 4 tires during the inspection. When they show tread wear in the red as in not the same they recommend all 4 to be changed. Whether this is just a way to make money who knows all I know is my rear tires where bald and the fronts had tread which where a sign that they had been changed at one point and the transfer case had failed.

Take it for what it's worth.

[F06msportmia]

Originally Posted by X Driver

In my opinion it is not necessary to change all 4. If you have 20s with different tyres they are not exactly the same even when they are new. Shouldn't be to much but wear is okay..

Agreed. I have 20's and at least in my case the rears where much faster than the fronts.

In the next couple of weeks getting new tires for the rear and still have a few months with the fronts.

With staggered you can't rotate for the obvious reason. A friend of mine a BMW tech did say that x5 should have at least the alignment done twice a year.

[Poppyboy]

Twice a year? That's the worst advice ever.

[lknbimmers]

Originally Posted by e70msportmia

Agreed. I have 20's and at least in my case the rears where much faster than the fronts.

In the next couple of weeks getting new tires for the rear and still have a few months with the fronts.

With staggered you can't rotate for the obvious reason. A friend of mine a BMW tech did say that x5 should have at least the alignment done twice a year.

Just replaced the front set of Continental DWS's, the rear tires were fine. The front set showed signs of outer edge wear. When I asked them to check the alignment everything was within specifications.

[094.8x5]

Originally Posted by e70msportmia

Agreed. I have 20's and at least in my case the rears where much faster than the fronts.

In the next couple of weeks getting new tires for the rear and still have a few months with the fronts.

With staggered you can't rotate for the obvious reason. A friend of mine a BMW tech did say that x5 should have at least the alignment done twice a year.

That's because of that silly ass rear end camber.....

[F06msportmia]

Originally Posted by 094.8x5

That's because of that silly ass rear end camber.....

Agree!

[smyles]

Originally Posted by lknbimmers

Just replaced the front set of Continental DWS's, the rear tires were fine. The front set showed signs of outer edge wear. When I asked them to check the alignment everything was within specifications.

Interesting, my front DWS's have the outer edge wear as well. And I don't recall having the same issue with my previous set of Toyo's.

[Ryan5034]

Just an idea here, if you are trying to save a buck or two, I've had good luck buying used tires on ebay that are the same make / model with the tread depth you need. It's pretty easy to find tires that would be within 3/32.

It's not ideal but hey if the rears still have a lot of life, then go find some fronts. I have also done this when I've destroyed a tire on the road and not willing to buy all 4 again.

[misterS3]

Of all the 4wd drive car's i've had/have only the S3 didn't have a staggered set up. And the advice is always change across the axle. I've never heard of having to change all 4 at once.

Also tyres are directional (well the ones i use are) so it's not so easy to rotate tyres these days. (i.e you'd have to take the tyre off the rim*)

*staggered setups