The complete automotive resource for buyers, sellers, and owners like you.
Car, Truck and SUV Forums at Roadfly
+ Bentley Forums
+ BMW Forums
+ Cadillac Forums
+ Chevrolet Forums
+ Ferrari Forums
+ Jaguar Forums
+ Lamborghini Forums
+ Lotus Forums
+ Mercedes-Benz Forums
+ Maserati Forums
+ MINI Forums
+ Porsche Forums
+ General Discussion
+ Marketplace Forums
Re: strange whine/hum over 45 mph (archive)
[ Follow Ups ] [ 7-series (E32) Message Board ] [ Msg. Board FAQ ]
Posted by Bryan HnlEuro635csi, 750il, E30 325i on July 30, 2001 at 01:59:52:

In Reply to: strange whine/hum over 45 mph posted by otis 88 735il on July 29, 2001 at 23:55:40:

Otis,
A couple of things to consider. Is the sound speed dependent or is it rev dependent? At the same speed 45-70 mph, try to downshift into 3rd gear and see if the humming changes. If it doesn't it could be something else. How are your tires? I got rid of humming on my 325 w/ new tires. Feel the tread of your tires in all directions front to back, back to front and in/out and out/in. They should feel the smooth, and the same in all directions. If not, they could be cupped and this could lead to your humming and even a slight vibration.

Over the last week I have noticed a strange whining or humming from under the car which starts at about 45 mph and gets louder until I get to about 70 mph. At 75 it goes away or the other road noises mask it. It does not go away if I am on the gas or not in drive or neutral. My guess is the center bearing on the drive shaft? I do not get a vibration yet or rather a very very rare one at 60mph which comes and goes, but feels more like wheel balance than underside driveshaft problems. This is getting worse and I am worried I will have to replace the expensive dreaded driveshaft. I can only hope the center bearing is the culprit. BTW, I was playing with the ride height adjustment for the hydraulic leveler underneath the car on the sway arm link and noticed two areas on the driveshaft before it enters the rear diff with wear lines like it is coming into contact with the body or something? Could that be the source of my sound? The sound does not sound like a rub or grind, but more like when bearings are bad and are starting to whine. Any thoughts I would love a cheap and easy fix. BTW, I have 128K on it.

PS Hope you don't get tired of me posting all the time, but I just recently bought this beauty and seem to have all the nitpicky things to fix. Tomorrow I have to pull the driver seat and fix both a backrest motor which has a short and the cable stretch thing for a twisted backrest. You do not want to know all the other things I have fixed, but they seem like the ones everyone else has done already. Thanks again.




Follow Ups:


[ Follow Ups ] [ 7-series (E32) Message Board ] [ Msg. Board FAQ ]
Questions, comments, or problems, please visit the Roadfly help desk.
Roadfly.com Logo © 1997 - 2009 Jump Internet Inc. All rights reserved.