Bearing Noise...AGAIN

[atillathetom]

I just called to make an appt to take my 4.8 in for its second bearing "fix".

I am concerned that they were unable to get things taken care of the first go 'round. I have searched the forums and it seems like it is a relatively straight forward fix. Is there anything you can point me to that would help the dealer with the repair?

The noise can be heard when performing an agressive 3pt turn or reversing from a steep driveway...sometimes just pulling out from a curb break onto the road. It is the very metallic pop that the service action describes.

Thanks,

Tom

[vinuneuro]

A bearing sound shouldn't be popping. The sound would more of be a humming/grinding sound going straight. While going straight if you cut the wheel hard one way, and you hear a grinding on the other side, you know the other side bearing is going. Another easy way to find out if it's the bearing..spin the wheel. If you feel vibration/resistance, you'll know what's up.

First places to look based on your description of popping, would be sway-bar end-links, lower control arm (balljoint), worn bushings.

[atillathetom]

I will have them look at those items too, but this is what the issue was last time.

SI B 31 01 05
Body Equipment May 2005
Technical Service

SUBJECT
Front Wheel Bearing Noise

MODEL
E53 (X5) produced up to January 2005.

SITUATION
Metallic knocking noise heard coming from the front axle area or through the floor panel.

CAUSE
The wheel bearing seat comes loose in the swivel bearing.

CORRECTION

Confirm the wheel bearing noise:

Bring the front axle components to normal operating temperature by driving and braking repeatedly for about 10 minutes.

Drive a complete circle with the steering wheel in full lock position to produce a high lateral acceleration.

Stop the vehicle and, with the vehicle in a stationary position, turn the steering wheel in the opposite direction for three turns. Do not turn to the full lock position.

Engage reverse gear and pull away abruptly. Listen for a brief, distinct metallic knocking noise to confirm the wheel bearing noise.

This Service Information does not apply if a rattling or chattering noise is heard.

The wheel bearing noise may be resonated to the transfer case via output shafts. Replacing the output shafts or the transfer case will not remedy the situation.

PROCEDURE
Once the wheel bearing noise has been confirmed, both front wheel bearings and drive flanges can be replaced by following the Repair Instruction RA 31 21 180.

NOTES

Ensure that the bearing press fit area is clean and free of oil and grease.

Coat wheel bearing seat in the swivel bearing over 50% of its length with either Loctite 648 (3 hours curing time at 70°F) or Loctite 638 (6 hours curing time at 70°F).

It is important to observe the curing time and the ambient temperature. It may take up to 24 hours curing time if either Loctite is applied at 40°F.

During curing time, do not move the vehicle or use brakes.

WARRANTY INFORMATION
Information only.

[ Copyright © 2005 BMW of North America, LLC ]

[vinuneuro]

Yes, the splines will incurr heat damage as a result as well. Maybe you have a bearing failure on your hands once again, but I'm not sure knocking is the word to describe it.

Logic: if it's the same noise as before, it's probably the same root.

[atillathetom]

Knocking is not the best way to describe the sound, but that is how it is written in the service action brom BMWNA.

Either way, I will let you know what the dealer has to say on Tuesday. I am also going to have them look into the transmission software...can't seem to get that right either.