BMW E90 rear wheel bearing: symptoms and replacement
How can you tell a BMW E90/E91 rear wheel bearing fault?
There is a hum or low rumble from the rear, typically at 80-110 km/h, and the noise grows louder over time. If the noise stops in one bend but continues in the other, it is probably the bearing. The first rear bearing usually goes at around 120-140 thousand km.
What other than the wheel bearing can hum from the rear?
The propshaft centre support bearing can cause the same drone at 80-110 km/h, and the noise only went away after replacing it. Tyres can also hum: if the noise does not change when cornering, the cause is more likely the tyres.
How is the rear wheel bearing replaced?
The bearing is pressed in place with a press, and a fairly large puller is needed to pull it out. When the new bearing is pressed into the hub, its inner ring is supported from the back so the bearing does not break. The exhaust hangers are opened so the drive shaft can come out. The job takes about 3 hours.