Loud groaning noise coming from rear end

[m3f_koolkat197_76a87646ad]

Hi everyone,



I just bought a 97 M3 Coupe 5spd with 63,850 miles on it. The car is in very good shape... inside and out. There's actually two issues that I'm having that I want to ask this forum. The first one is more important. Whenever I am in the 20mph - 25mph range, I hear this loud groaning noise coming from the rear end. I've been reading the past couple of days on different BMW forums and everyone seems to think that it has to do with the differential fluid needing to be change and adding a LSD additive. Have anyone here share the same experience. From what I can tell, getting the Redline 75W90 gear oil will do the trick. I can use this oil without any additive... correct?



My second problem is whenever I press or depress the cluth, I hear this squeeking noise. Its not a major issue... but just rather annoying. I tried spraying WD40 on the springs behind the clutch but that didn't seem to do the trick. Is there another place I need to spray WD40 to to get rid of this annoying squeeking noise? Please advise.



Thank you in advance.



Kiet

[m3f_raycer]

Congrats on your purchase! I posted the same problem a few weeks back. Most of the reposnse pointed to the differntial fluid, but given that I had just had all the fluids changed, I did not think that was actually it.



A few people mentioned that dealers have told them it was the way some of the bushings are in these cars, and it was normal. I kind of understood the bushing thing, but was not buying that this is "normal".



Whatever it was, I have noticed it much less frequently and am attributing it to some sort of part that was replaced by my mechanic which just needed to loosen up a bit -- e.g. a tight bushing.



No idea on the clutch. I would suggest a bit of WD40, but it seems that you already tried that without much luck. Not sure....



Enjoy the car!

[m3f_koolkat197_76a87646ad]

Hey Raycer,



Thanks for the response. I will definitely try to change the differential fluid and see if that helps the noise any. The question I still have is if I use the Redline 75W90 oil, do I still need to get the LSD Additive (GM or etc)? Please advise.



Oh yeah... and the clutch squeaking noise... its still very annoying. Thanks.



Kiet

[m3f_fitchesbas_a4754265ce]

The clutch problem can be solved by getting the UUC Motorwerks Clutch Arm Bushings. you can read and order them here: http://www.uucmotorwerks.com/html_product/clutch_arm_bushings/



Although good luck getting them in a timely manner. I waited a month and a half for tranny mounts and am stilling waiting on an exhaust i ordered in mid june. UUC's products are good but their backorder is killing their business....they told me june 20th "you should have your exhaust in 2 weeks shipped" hmm still dont have it.



Anyway had to rant!



Good Luck!

Derek

[m3f_99DakarM3_146594ecf1]

Just get some white lithium grease on the bushing for the clutch and it should be fine for a while.



UUC is about the worst vendor I know when it comes to shipping - if you can't get their product from an aftermarket retailer, or if its not in stock I wouldn't even bother ordering from them.

There's too many other companies with just as good products that will save you hours of headache and hassle - and of course days, weeks, even months of waiting.

[m3f_tdwyatt]

on your groaning noise, does this occur when the roads are wet or under slippery conditions? Your traction control system will on occasion make groaning sounds when applying braking force to slipping wheels. Deactivating it may not be the smartest thing to do under those conditions, but it will stop the noise if this is what is occurring.



Just a random thought...



HTH

[m3f_Sirius_880bd69485]

It could be a wheel bearing too.



You need someone to pinpoint where the noise is comming from.

[m3f_koolkat197_76a87646ad]

The noise is only happening when the car decelerate to 15-25mph. When it goes past this range, the noise is gone. It may also be occuring when I'm accelerating and its going through this range... but not as noticeable. Everywhere I've read saids that replacing the differential fluid will do the trick. So I ordered the Redline 75W90 fluids and will be swapping out the fluid as soon as my mail ordered 14mm hex socket arrives. I hope this does the trick.



If the wheel bearing was the issue, would that cause noise throughout my drive? Thanks again.

[m3f_koolkat197_76a87646ad]

Ok... I changed my differential fluid today with the Redline 75W90 fluid. I took the car for a spin after the change and unfortunately, the noise is still there. Again... its a noise that only occur when I'm accelerating to 20-25mph, or decelerating to 25-20mph. I'm just not sure what the problem may be. Its a low loud vibration type noise... it even cause my rear view mirror to vibrate a little when the noise is occurring.

[m3f_Sirius_880bd69485]

I wonder if you have a broken tranny bracket.

[m3f_dboffa_1e4798cde8]

I've heard that a worn or incorrectly installed/tightened guibo (flex disk) can cause some strange vibrations.

[m3f_romh_9db5ad5d95]

Couple ideas.

I have the same noise/vibration in that mph range. Actually, mine even occurs at 40 or 50 mph when I deccelerate at any gear. Weird. Mechanic says that it is more than likely a bad tire. He explained to me that usually, all 4 wheels turn at a different speeds. Therefore, it could be that one bad tire is causing that noise when it is turning at a different speed than the others. He might be right / wrong. He also talked about it beeing the driveshaft bushings.

The thing concerning your clutch squeak. I've had it forever. My mechanic friend at the BMW dealership that's worked there for 10 years says that it is only two things. Either the little spring behind the clutch pedal which needs to be oiled, in which case you have already oiled up. If its not that, then its the other much harder option to fix. Its the throw out bearing which slides over some metal piece which has oxidized slightly . The only way to access this and relubricate/clean this slide is to take the whole clutch apart. He says, that once you do this, then its makes much more sense to put in a new clutch, considering that a clutch only costs like $150 while the whole labor to do this runs like (7x$105 = $735 at dealership).

There it is. He also pointed out that he did this procedure many times when our cars were under warranty when customers brought it in complaining about the squeal. If I would have known that, i would have taken it years ago. But considering that my 1995 civic ex also had the same squeaking noise, I thought it was normal for manual trannies.

I've gotten used to the squeal though.



Hope it helps. Let me know what solves your roaring noise.

[m3f_Sirius_880bd69485]

Yeah, I fixed the clutch squeek inside the car, still hear it outside.



No way in hell I am taking off my tranny to fix a squeek lol.

[m3f_romh_9db5ad5d95]

Yeah, I fixed the clutch squeek inside the car, still hear it outside.



No way in hell I am taking off my tranny to fix a squeek lol.



I know this is a super off topic. But your headlights look awesome! I never get tired of looking at them. Can;t wait to do mine some time.

[m3f_koolkat197_76a87646ad]

I think my next step is to replace my rear tire. They're both pretty worn out and there's some uneven tread on the inside of the rear tires. I'm hoping one or both of those tires are causing the problem.