Yes, the hub is identical
Same 5x120 PCD and same 72.6 mm centre bore: wheels from Alpina B4 axe arrière bolt on and centre on BMW X6 E71 axe arrière without rings. You still need to check the offset and tyres, detailed below.
≈: width estimated from the original tyre size.
Wheel by wheel: offset and tyres
Each original wheel from Alpina B4 axe arrière is compared with the one from BMW X6 E71 axe arrière of the same diameter: how much closer the wheel gets to the shock absorber or how far it sticks out of the wheel arch, and whether the tyre keeps the same overall diameter.
- !
≈7.5Jx19 ET47 · 245/35R19 — Check on the car
Compared with the original 9Jx19 ET18 on BMW X6 E71 axe arrière: shock absorber side +9.9 mm, wheel arch side −48.1 mm, tyre diameter −11.3 % : fit it with the original tyre size of BMW X6 E71 axe arrière (255/50R19), not that of Alpina B4 axe arrière.
Comparison for guidance only (estimated width). Check in detail
Before fitting the wheels
An identical hub is not enough: offset, width and diameter change the position of the wheel, and larger calipers can touch a smaller wheel. Original wheels often use bolts or nuts with a specific seat: keep the fixings intended for the wheel, with the thread of BMW X6 E71 axe arrière (M14x1.25), tightened to the torque shown on its vehicle page. Finally, check that the size is among the approved fitments for your vehicle. This comparison is for guidance only: have the fitting approved by a professional.
And the other way round: wheels from BMW X6 E71 axe arrière on Alpina B4 axe arrière?