[PrematureApex]

Originally Posted by eugenelt

Just asked a local tire shop, they said 16" wheel will not clear.

As posted above, might depend on which size front rotor you have (I think we determined a couple weeks ago that there was a change to larger front rotors at some point). If they're 330s, a 16 is going to be tough, but if they're the 314s (or whatever the smaller one was), you might be OK. E90 328s with a 300mm rotor run 16s easily, and you'd only need 5-8mm of clearance.

I'd search on the E90 forums a bit more for insight.

Originally Posted by eugenelt

However, they also said "anything that is taller or shorter will throw off your 4WD system", referring to my 215/60R16. Given that the actual circumference difference between 225/50R17 and those are about 1%, which I mentioned to them, I don't see how it would influence 4WD.

Basically I think they're making an uneducated guess, so I'm a little doubtful they've actually tried to fit 16" wheels to X1. Will ask my mechanic, I guess.

The shop is wrong. You can run larger or smaller overall diameters front and rear with no affect at all on the AWD system.

More generally, IIRC, BMW's xdrive can also tolerate front/rear diameter differences, which not all systems can. But regardless of that, running the same (larger or smaller) size front and rear is 100% fine.