[fortythirtyfive]

Originally Posted by aerobod

I see from your signature that you have spacers on the wheels, there is quite a dangerous condition that could be causing the noise. It is dangerous enough that I saw an M2 lose a wheel at 140km/h on the track in July due to this problem, causing thousands of $ in damage to the bumper, suspension, wheel and brake, but luckily the car was brought to a stop without a crash.

The hubcentric flange on some wheel spacers has a chamfer that is larger than the chamfer on the wheel, this causes the wheel to not sit flat on the spacer, putting excess force on the wheel bolts (or in the case of the M2, the stud conversion kit). Eventually the bolts or studs will fail from cyclic fatigue loading as the wheel moves about a very small amount on each rotation.

Here is a method from Bimmerworld to check if you have a problem, besides looking at both the hub chamfer and spacer chamfer for signs of fretting (small movements that will produce abrasion marks):

If this is the problem, the spacers should be replaced with ones that don't have the problematic chamfer and all wheel bolts that have been used with the spacer should be replaced too, due to unknown loading conditions that may have weakened them.

The vehicle makes the noise without spacers unfortunately, thanks for the info though! It made me go and check my existing spacers and luckily they all fit perfectly.

In total I have now tried fitting new wheel bolts, new pinch bolt (greased), peeled back the pinch bolt collar, fitted friction plates behind the brake disc (between the hub) and also between the brake disc and wheel and still no avail.

The noise is actually super loud this time and is definitely turning heads on the street lol. No garages seem to be able to put their finger on it and when they feel they've fixed it.. it comes back within a day or two which is most likely due to the wheel being lifted in the air ☹️ so at this point I'm avoiding driving the car as it's kind of embarrassing to hear