New noise in '99 540/6: clutch or tranny? Arrgh!

[Eric S.]

My fun-to-drive money-pit developed a new, barely perceptible noise yesterday. At first I thought it was the A/C blower because it sounds a bit like low-rpm fan blades very slighty hitting cardboard. I have only noticed it at parking lot speeds. This morning I did some cause-effect experimentation with it and discovered that varying my fan/blower speed had no effect; however, whether I had the clutch in or not definitely controlled the noise, as well as whether I was in neutral or in gear.

I am thinking it's clutch-related, maybe a throw out bearing, since the noise doesn't seem to care whether it's in 2nd or 3rd (parking lot speeds, remember). I am at 128K miles and most likely still on my original clutch, which I was hoping would last until bonus time next March (since it's at least a $1500 job). Anyone want to weigh in with a diagnosis/opinion? Anything else I should do to check/confirm? Anyone? Anyone? Thanks!

[LOS]

Maybe you're right about the clutch being original. Highway miles are the best for any car. I live in suburb close to L.A and let me tell you, there are traffic lights almost on every block!
Anyway, as you mentioned, the risk of damaging anything else is low. I would keep driving the car until the issue really gets worse.
I'm going to search on clutch write-ups and see what comes up. Sometimes is better to have someone else do the work since they already have the special beamer tools!:

LOS

[LOS]

check this out...

http://www.babcox.com/editorial/bf/bf50332.htm
http://bimmer.roadfly.com/bmw/forums/e39/7792010-1.html

Dang, now I know why the want $1500 for a clutch job!:

LOS

[Eric S.]

Originally Posted by LOS

check this out...

http://www.babcox.com/editorial/bf/bf50332.htm
http://bimmer.roadfly.com/bmw/forums/e39/7792010-1.html

Dang, now I know why the want $1500 for a clutch job!:

LOS

Thanks man, this is all I have so far other than what you found:
http://members.cox.net/anmillar1/index.htm
I'd give you more props, but the Board won't let me! Got to get you on that "Distinguished Road"!!!

I'd say right now that my symptoms most closely resemble "chatter"...

[Eric S.]

More Noise Details:
After listening further this morning, I am convinced that the sound is in the clutch/flywheel/TO Bearing area. So far, I am only hearing it when decelerating (under engine braking) at residential neighborhood speeds, peaking at about 15 mph. It sounds like holding a card in a fan or a kid’s bicycle spokes* and can easily be heard outside the car. The frequency sounds exactly like a match to engine rpm. If I press in the clutch, the sound immediately stops, so it’s only when under reverse loading that it makes the noise, at least at this point.

On that note, I’ve checked UUC and their “normal” (non-dual mass) flywheel & Sachs clutch kit is an eye-popping $2450. I think I’ll stick with stock/OEM! All OEM autoparts dot com has the LUK flywheel (OEM?) for under $600 (Crevier quoted me $700) with free shipping and the Sachs clutch kit can be bought from them for $363 or I can go to getcoolparts for about $342. On the other hand there’s BAV Auto’s Sachs kit for another $100 at $449 that includes the rear main seal and some other goodies. Thanks to H8LUUZN & others, I know that I need to replace the heater core hoses and rear main seal while I am in there, and would also like to upgrade to an M5 shifter as well.

So it’s all very confusing, especially because I don’t really want (or have the facilities) to tackle the job myself, but have only one Indie option here in Richmond VA, Twin Star, which would be almost as much as the dealer. The dealer wants $95/hr but offers a 15% discount to CCA members, whereas Twin Star now gets $80 per hour. A trusted friend of mine who is a Honda specialist (he won’t touch anything else) recommended a Tech who works at Twin Star, but I found out yesterday that person will not consider doing any work “on the side” outside of Twin Star, so I don't know where to turn...

[LOS]

The write-up was great...
Try to stick to OEM parts if you can. When it comes to transmission/clutch issues, you have to get it done right the first time. I think this is going to cost you an arm & a leg... But hey, we love our cars!

LOS

[Torque]

Most likely throwout bearing and/or clutch. My Subaru had the same thing when I bought it. New clutch kit, flywheel resurfacing solved all the chatter and rumbling.