# What does it take to get the differential whine fixed?



## bmw325 (Dec 19, 2001)

jpherit-

I also have a 2001 325i manual. My symptoms were exactly the same as yours. Call your dealer about getting the butyl strip for the center bearing (there is a TSB for this). They may say that it doesn't apply to your car, but just keep insisting-- i'm 99% sure it'll fix the whine you're describing. I guess I wasn't alone w/ this noise. Funny- I used to post about this problem (before I found the solution in an old bimmer.org post) and it seemed like no one ever heard of it- but now it seems like many have it!


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## 31st330i (Jan 11, 2002)

jpherit said:


> *Thanks for the thought.:thumb: *


that's just what the mechanic is going to do so you might save yourself the time and agrivation of making an appointment at the dealership only to get the car back with those famous words: "could not duplicate. no problem found." plus he might put the detailing monkey in the car then raise it up on the hoist and listen to the differential with a mechanic's stethascope for bearing and/or gear noise.


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## bmw325 (Dec 19, 2001)

Once you know how to do it -- its actually pretty easy to make this whine happen. So, go for a drive w/ a dealer mechanic and do the following:

get up to about 70mph. Ideally, find a section of highway that is slightly downhill- and apply very partial throttle. The shop foreman at my dealership actually drove my car and knew exactly how to get it to come out -- he did it better than I could do it-- it was really singing! But definitely don't just take it in and decribe the problem-- make them go for a ride and tell them what the solution is.

31st330/jpherit-

You actually don't need to sit in the back to hear this noise-- the center bearing support transmits the noise to the body and it will actually sound like its coming from the passenger footwell area (for some reason)-- if you lean your head closer to the gearshift area, you're hear it very well. And, if you drive it under the conditions I described, you should be able to get it to come out very noticably for any mechanic. In sum, the front seats are actually the best place to hear this noise. I'm sure that even w/ the strip in place, if you sat in the back seat and payed close attention you'd hear the differential-- I can still hear mine faintly- but only because I'm so attuned to the pitch now.


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