Uh Oh...Rear Differential Problems...
Here's the dealio:
I've had a vibration in the rear end for sometime, and has recently gotten worse. I put it on jacks and hand-spun the rear wheels, and it sounded like a rythmatic, rotational flat-spotted bearing inside the diff. Car is a '99 323i with 165,000 on the ticker. Does anyone know of these having diff. problems later in their life? The vibration can be felt at all speeds, but is the worst between 30 and 40mph, and when accelerating it is amplified. It also gets amplified around corners. I know it's in the diff. because I disconnected the output shafts and rotated the driveshaft and it still made the same noise.
Here's what's been replaced since I've had the car:
- Front struts and rear shocks
- Trans./driveshaft rubber coupling
- Center carrier bearing assy.
- Rear wheel bearings
- All brakes and related components
- Wheels and tires
I did not check the fluid level, nor has it ever been replaced to my knowledge. However, the entire diff. and surrounding area are bone dry...No signs of any leaks. The only thing I haven't replaced are the output shafts...The inboard joints at the diff. felt a little worn and stiff, but as I mentioned before, the noise still comes from the diff. with the shafts disconnected. And yes...I'm going to replace the output shafts - To my knowledge, they are the originals as well. Expensive buggers, though.
I guess my question(s) is: What's the problem? Bearings in the diff. housing? Gears? Old Age? Is my differential repairable, or should I just call some 'yards and try to find a low-mileage diff? Does BMW have a reman program?
Any help/insight would be greatly appreciated.
Thanks in advance.
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