The newer X5's hub size might be different and that's why hub rings are required to center the wheel properly on the hub.

The rings are not only for aftermarket wheels. I had to install rings on my 88 M3 when I went with E39 Style OEM wheels as the hub size was slightly different.

__________________

1987 E30 325i - Sold
1988 E30 M3 AW/CR -
1997 E36 M3 Cosmos Blk/Blk- Sold
2001 E53 4.4i/TSM/Blk/ZCP/ZPP/ZPS/ZRC/ZSP/Nav/PDC - Sold
2006 E90 330xi/MB/Terra/6 spd/ZSP/ZCP/ZPP/Nav/PDC/CA/SSK/BMW Performance Exhaust/CSL's/Blk Kidneys - Sold
2008 E93 335i SGM/CR/6MT/ZSP/ZPP/ZCP/Nav/PDC/CA/230's/JB+/Dinan CAI/BMW Perf SSK/Kidneys/Handbrake - DD
2008 E70 4.8i BSM/Blk/ZCP/ZPP/ZPS/ZSP/ZTP/ZRC/CA/Rear Ent/HUD/214's/BMW Perf Kidneys