BMW X5 & X6 Wheel Specs

Background

The E70 X5 and the E71 X6 have a lot in common. One of the few areas where they differ is in the rear axle hub and wheel center bore. It's the center bore that this page will focus on the most as that seems to be the root to all of the confusion.

For some reason, BMW used two different center bore dimensions on the E71 X6, the E70 X5M, and the E71 X6M. The front axle has a 74.0mm hub while the rear axle uses a 72.5mm hub. All other 2007+ X5/X6 models use a 74.0mm hub on the front and rear and the first generation X5 (E53) uses a 72.5mm hub. We won't speculate on why BMW released a product this way or what the engineering reasoning is. The 72.5 hub part number is not shared with any other BMW so it was not lifted from the parts bin. And why they didn't borrow the same part from the X5 is a mystery.

It's interesting that the rear axle and rear axle nut are not specific to these models; they are shared among the various X5/X6 variants. This leaves open the possibility that the E70 rear hub could be swapped over to the E71 to standardize the fitments. We have not done this to confirm the theory and there may be other factors at play. But speaking hypothetically, it seems promising. You would then have to run matching wheels, which can be accomplished easier than swapping the hub flange (see bottom of page).

Here is the parts diagram for the E71 X6 rear axle:
#1: hub flange in question
#2: rear wheel bearing
#3: fastening bolt
#4: rear axle nut
#5: dust cover

Parts Matrix

Below is a table of the front hub part number, front hub size, rear hub part number, rear hub size, and bolt specs. The table is sorted by common hub sizes and part number to better identify which models share sizing.

MODEL	FRONT HUB	HUB SIZE	REAR HUB	HUB SIZE	BOLT
E70 X5	31226867808	74.0	33406867811	74.0	14x1.25
F15 X5	31226867808	74.0	33406867811	74.0	14x1.25
F16 X6	31226867808	74.0	33406867811	74.0	14x1.25
F85 X5M	31227850161	74.0	33417850162	74.0	14x1.25
F86 X6M	31227850161	74.0	33417850162	74.0	14x1.25
E71 X6	31226867808	74.0	33416776205	72.5	14x1.25
E70 X5M	31226867810	74.0	33416776205	72.5	14x1.25
E71 X6M	31226867810	74.0	33416776205	72.5	14x1.25
G05 X5	31206864571	66.56	31202408656	66.56	14x1.25
G07 X7	31206893781		31206893780 31206895673		14x1.25

Wheel Sizing & Specs

To compare wheels we're going to look at the most aggressive BMW factory fitments for each model. However, we are going to stop short of making actual size, offset, and retrofit recommendations because it would be irresponsible for us to do so without confirming fitment in our shop. We will provide you with the data and let you reach your own conclusions. Note that these are the most-aggressive wheel fitments that BMW offered as factory options. All of the below wheels will require the factory fender flares (extensions) to better cover the wider wheels and tires. As always, if you need further assistance on what this data represents, please give us a call or email.

MODEL	FRONT SIZE	FRONT OFFSET	REAR SIZE	REAR OFFSET
E70 X5	21x10.0"	ET40	21x11.0"	ET42
F15 X5	21x10.0"	ET40	21x11.5"	ET38
F16 X6	21x10.0"	ET40	21x11.5"	ET38
F85 X5M	21x10.0"	ET40	21x11.5"	ET38
F86 X6M	21x10.0"	ET40	21x11.5"	ET38
E71 X6	21x10.0"	ET40	21x11.5"	ET38
E70 X5M	21x10.0"	ET40	21x11.5"	ET38
E71 X6M	21x10.0"	ET40	21x11.5"	ET38

X5, X6 Fender Flares

For the more aggressive wheel sets (20" or higher), BMW used a set of bolt-on fender flares / fender arch extensions to better cover the wider wheels and tires. These are a direct replacement for the existing, smaller fender trim. Without the flares, the tires "poke out" from the fender. Unfortunately, it adds some extra cost to a X5/X6 wheel upgrade but necessary.

Conclusion

Taking the data from the above two charts, what can we surmise? Wheels from an E71, E70 X5M, and E71 X6M are interchangeable with each other. However, those wheels will not fit any other X5/X6 model. E70, F15, F16, F85, and F86 wheels will fit those other models but will require a wheel centering ring on the rear axle. Note that all of the above wheel specs require the factory BMW fender flares (extensions) to better cover the wider wheels and tires. These flares were standard on M models but will need to be added to non-M models.

For any questions on wheel fitment, specs, interpretations, or technology, don't hesitate to call or email our parts advisers.

More BMW Wheel Info & Tech

Looking for more info on BMW wheel technology, fitment data, or general info? Check out our main Wheel Info page by clicking here.