H&R spacers decoded
 

OK, got a third and fourth call from Stephanie at H&R regarding X5 spacers. Seems they're serious about getting to the bottom of the spacer part number discrepencies as we are. So here's the scoop for the 25mm (30 would be similar):

50757251, 50757252, 50757255
Let's break it apart- 50 75 725 X
50 means 50mm total width (2 spacers of 25mm each)
75 means a BMW with 5x120 bolt pattern
725 means 72.5mm center bore
Then the mysterious number on the end:
5 is a DRM spacer with studs to convert your X5 from bolts to studs and nuts.
1 is a DRA spacer which comes with 25mm bolts to attach the spacer to the hub.
2 is the same DRA spacer but with 30mm bolts to attach the spacer to the hub.

Seems the engineers in Germany thought of everything when designing the spacers and tried to build sets that tuners could use for their own needs, including big brake kits with thinner rotor hubs (25mm bolts) than stock rotors (30mm bolts).

FWIW- the 30mm spacers would then be 60757252.

Guess it's time to order up my 50757252 spacers.

Excellent detective work :thumbup: Please post some pictures during and after the install?

Will do. Frankly I just need some nice weather (and a chance to get out of my office by daylight) to take some pics of the X5 as it is now. 3 months and no pics yet.

thanks for this Help. I called H&R and they only listed the 50757251 now. you can still buy ...7252 from online sellers, and in black :)
I had someone pull two inserts out because they over torqued them. So I MAY have to buy a whole new set if H&R can't get me the inserts alone. They do have a part number, sdo they are looking into whether they sell them separately.