Went to 20s and need help

[Driver8]

One quick thought, Mickey - IIRC, on my '02 X5. the front wheels did not require centering rings, but the rears did. (Odd setup, that...)

I would start with the centering rings first. Are they intact? Damaged? Seated correctly? Some of them fall out with little provocation. Plastic or metal? The plastic ones can become deformed or can be mounted off-center. I'd look there first since this is an easy thing to mark off the list. These wheels and tires have a bit more unsprung mass than your OEM wheels, so any imbalance will be very noticable. One question: Do you feel the vibration in the steering wheel or the seat/pedals? If it's in the steering wheel, look in the front first. Otherwise, start in back.

Regarding an alignment...it's a good idea to do one when you mount new tires just to make sure everything is in spec. Have it done at a BMW dealer as they have very specific guidelines they use to perform the alignment (i.e. weights in the seats, trunk, etc. to simulate a loaded car).

I've pulled my hair out over centering ring issues in the past with other cars, but I never had any problems with my 20" Style 87 replicas. Good luck!

Mike