Tires

[BDO]

I’m coming up to the point where the tires will need to be changed.

1. Why have my fronts worn quicker than the rears? I thought the xdrive is rear-biased? I couldn’t rotate them as I am on a staggered setup.

2. Is it true that due to transfer case reasons, I have to replace all 4 at the same time? If so, again, with the uneven wear between front and rear, isn’t the transfer case taking damage already?

Thanks!

[meds1976]

No need to change all 4. But don't mix and match if possible i.e. same type of tyres across each axle.

[BDO]

Originally Posted by meds1976

No need to change all 4. But don't mix and match if possible i.e. same type of tyres across each axle.

Of course, I’ll be sticking with the same brand so they will be the same front and rear.

But really confused about the 2 vs 4 approach now since everything I’ve read so far insists that transfer case damage is guaranteed unless changing all 4 on an xdrive SUV.

[meds1976]

As long as the tread level isn't too far off, you'll be fine.

[BDO]

Originally Posted by meds1976

As long as the tread level isn't too far off, you'll be fine.

How much wear is ok (on the rears) to be used with new fronts?

So many threads on this forum insisting that all 4 must be changed to avoid certain transfer case destruction 😄

[tfunk88]

It’s the difference in diameter that matters. If there is more than 1% difference then it puts strain on the transfer case.

For example, Michelin PS4AS have a diameter of 28.7” when new, and a tread depth of 10/32. If your rear tires are a little more than half worn and you put new tires only on the front they will be outside of the 1% difference the transfer case can handle. Which is why so many people say to replace all 4 tires at once.

[BDO]

Originally Posted by tfunk88

It’s the difference in diameter that matters. If there is more than 1% difference then it puts strain on the transfer case.

For example, Michelin PS4AS have a diameter of 28.7” when new, and a tread depth of 10/32. If your rear tires are a little more than half worn and you put new tires only on the front they will be outside of the 1% difference the transfer case can handle. Which is why so many people say to replace all 4 tires at once.

This is consistent with what I’ve read. I’m pretty sure that the rears are more than half worn - which still means I’ll be throwing away rubber with quite a bit of life left.

But one thing I’m curious about - is the TC already taking damage due to a different wear between fronts and rears?

[tfunk88]

Not unless the difference in wear is crazy different. If fronts were down to the wear bars (2/32) and the rears were still at more than 6/32 tread then yep. But that’s pretty unlikely…unless you’re somehow doing front end only burnouts lol

[m4forum]

Personal experience .... few month ago I decided to rotate tires between front / rear in order to prolong tire life as notice some difference in wear between both axles ... not much. As soon I drove around the block noticed the car was jerking slightly ... return the tires to its original position and issue went away.
Bottom line : tire circumference is very important. I plan to replace all tires.

[Qsilver7]

Look at the DOT date on the tires. If they are the original tires…and you have a 2016…the tires may be at their replacement date. Tires have an “age” life span of approx 6 to 10 years. If you have the funds…perhaps it would be a good time to go ahead and replace all 4 tires if they are between 6 to 10 years old…along with the low tire tread.

[BDO]

Thanks all. Ordered all 4.