loud hum, wheel bearings?

[mjfeeney4]

Before ordering parts to replace the from wheel hub(s), I was wondering if this sounds ( no pun intended) like a worn wheel bearing. What can be best described as a loud hum, similar to aggressive tread off-road tires used on trucks, has been comming from both sides of the front end. Getting progressivly loader over the last 6-12 months. The 91 525 has 164K mi. No relationship to engine RPM, and no difference on various road surfaces.

Other posts describe a sound that is louder when turning (at higher speeds), but mine has no grinding sounds and no difference with turns. The sound does get louder with high speeds, and it is almost inaudible below 25 mi/hr.

Befor ordering from BMA, do others agree that the bearings are shot??

[Rory535i]

yeah definately the wheel bearings.

[mjfeeney4]

yeah definately the wheel bearings.

Nothing worse than fixing the wrong part. Appreciate the feedback.

[mjfeeney4]

Jacked the rear end so the wheels could spin freely and the noise is coming from the back end. It is difficult to tell exactly but it appears the passenger side is louder. Any ideas on how to tell if the problem is the rear differential or rear wheel bearing. One clue is that the hum is more noticable from the inside of the car, than the outside.

Mike Feeney

Before ordering parts to replace the from wheel hub(s), I was wondering if this sounds ( no pun intended) like a worn wheel bearing. What can be best described as a loud hum, similar to aggressive tread off-road tires used on trucks, has been comming from both sides of the front end. Getting progressivly loader over the last 6-12 months. The 91 525 has 164K mi. No relationship to engine RPM, and no difference on various road surfaces.

Other posts describe a sound that is louder when turning (at higher speeds), but mine has no grinding sounds and no difference with turns. The sound does get louder with high speeds, and it is almost inaudible below 25 mi/hr.

Befor ordering from BMA, do others agree that the bearings are shot??

[niall]

the diff is a possibility but i think more likely wheel bearings, they are a cheaper fix aswell!!!

[Mobius]

A hum related to the differential or the CV joints would most likely be more noticeable when you're on the gas. If the hum is only relative to rolling speed and sounds no different when accelerating hard, it is most likely a wheel bearing.

Get someone to stick their head out of a passenger side window and see if you can comfirm that its coming from the rear. It seems like rear bearings are a bit longer-lived than the front.

I've got a front hub/bearing in the mail right now. Now I have to figure out how I'm going to measure 214lb/ft of torque.. :\

[mjfeeney4]

Futher tested by jacking only one side of the rear and the problem now appears to be isolated to the rear passanger side. I should have included that the noise started with the dreaded ticka ticka ticka sound about 1 year ago, but now has been replaced by the hum.

The sound does not appear to be effected by engine RPM or transmission gear, only the speed of the car.

Have I limited the source to rear wheel bearing?

Mike Feeney

[Mobius]

Futher tested by jacking only one side of the rear and the problem now appears to be isolated to the rear passanger side. I should have included that the noise started with the dreaded ticka ticka ticka sound about 1 year ago, but now has been replaced by the hum.

A 'tick' would be less likely a wheel bearing and more a CV joint.. Check your CV boots back there for any tears or leaking.

Still, if it was a CV joint issue, it should change with torque. Also, failing CV joints don't typically 'hum'.

If the boots check out, I think you're safe to assume it's the bearing.

[atomicDog]

I'm having a similar problem with my 1995 525iT. I'm planning to replace the front wheel bearings on my car soon, as they have over 141,000 miles on them.

Anyone know what size socket is required to remove the wheel bearing retaining nut?

[Mobius]

I'm having a similar problem with my 1995 525iT. I'm planning to replace the front wheel bearings on my car soon, as they have over 141,000 miles on them.

Anyone know what size socket is required to remove the wheel bearing retaining nut?

http://www.bmwe34.net/e34main/mainte...eelbearing.htm