Staggered tyre set up 40d

[Mr black]

Do the rear tyres generally wear quicker than the fronts?
What is the max difference between the front-rear the xdrive and transfer box can tolerate,mine is 7mm front 5mm rear at the mo.

Thanks in advance.

[X5Sport]

Yes, the drive is predominantly RWD once you are moving.  I would avoid going much more than 2mm front/rear difference.

[Mr black]

Wow 2mm that’s crazy so I could be looking at new rears 

[X5Sport]

Welcome to BMWs poor design choices in how the xDrive system works and materials used.  It’s something silly like 1.5% difference in the overall circumference.

If it isn’t making noises now, or jerking at low speed on full lock you are most probably fine as you are, but keep an ear on the systems.

It is also fair to state that it doesn’t happen to everyone, and it is an increased likelihood but nothing concrete to say what definitely will or won’t cause an issue, or what tyres seem to be more prone.

The latest cars are less of an issue and more tolerant.