secondary wheel question

[BMW X5]

may have been asked before but . I've got 2013 3.5M-Sport, currently sitting on 20" M style. I want a second set for the winter. any suggestions on whether to go 19" or if already doing it to go with 18" and in either case which would be the right wheels to fit without any customizations. additionally is there anything factory to be done about the offset on the smaller wheels or just live with it for 3 months?

[BMW X5]

[Price]

I'd say go with whatever you can find cheap - people upgrade to 20s and sell 18s and 19s. But with all things equal I'd go with 18 - tires probably will be slightly cheaper and better selection.
Wouldn't care about the looks, but if it bothers you, get a set of spacers.

[motordavid]

IIRC, your E70 M wheels have a hub bore of 74.1...
whether you go to 19" or 18", that hub bore is the parameter, other than having E53 wheels machined/enlarged to the E70 larger hub bore diameter. Also, from fading memory your OE wheels have an offset of ~18...

OE and some rep wheels with that proper hub bore size should bolt on with no problem, esp if wheel bolt size is identical: M14 x 1.25.

Haven't memorized all the OE wheel offsets, but I suspect 19s or 18s may have a more 'normal', higher number offset. That should not be a problem other than cosmetics, as a less offset wheel, esp smaller diameter, will sit more 'inside' the wheel well, looking down the body line, and carry a less wide tire.
My 50Cts...
GL, mD

[BMW X5]

awesome thanks for the feedback. just need to look for e70 18" before the next season.