Noise sounds like metal on metal brakes on 318ti - maybe driveshaft?
 

Hi folks,

I just recently bought my 1995 318ti (108000mi)- I have experience with Porsche to some extent (I used to work for Inskip Porsche) but NONE with BMW! So I will most assuredly sound like a bonehead to the majority of you! I have a strange rotational noise that almost sounds like metal on metal brakes, or like tires on a wet roadway. It only happened within the past couple of days when it was 25 degrees Fahrenheit outside. I wonder if it may be a drive shaft noise? I pulled the front wheels off, brake pads look great, the wheels spin freely, everything seems fine. Any ideas???

explain the sound more...if its the driveshaft you should hear more of a whinning, or a spinning action. it could be something loose and running against the ground did you go over anything? it might be the brake shield hitting the rotor. where is the sound coming from? the front, rear, or middle. i doubt the weather would produce the sound

Further Description of Noise
 

It's a spinning rotational kind of noise that almost sounds as if a backing plate is making contact with one of the rotors, but I checked those when I removed the front wheels. The sound seemed to me like it was coming from the right front, but it is DEFINITELY more audible in the cabin than it is outside of the vehicle.

It is a scraping, metallic, metal on metal noise that happens as soon as the vehicle starts to move and does not change in character when the weight of the vehicle is thrown around (i.e. like a wheel bearing would be expected to do)

Hope this helps with the clues!!!

Thank you!

have you checked the pads? you might have a rock stuck under the pad.

Questions:
Does it change with pressure on the brake pedal?
Does it change with car speed (while in neutral)?
Does it change with engine speed (car stopped)?
Any vibrations?
Left or right, worse or better, or no change at all?

Driveshaft center load bearing?

Strange Noise Continued...
 

- yep, I had the wheels off and checked the pads for stones, pebbles and fine jewelry = nada....

- The noise happens if the vehicle is in neutral and just rolling. Really, the best way that I can describe it is imagine a metal on metal rotational brake kind of noise, but it doesn't change when hitting the brake, RPMs have zero effect on it. It does get louder and softer as speed increases.

Weird

Some people have had problems with the heatshield around the catalytic converter hitting the driveshaft. Seems to be more of a problem when it is cold out.

RE: Cat heat shield
 

I'll give that a look and report back. I miss having a lift at my disposal!

Thanks for the insights! This is an excellent forum!


RK

I have seen spring clips touching the rotors before which would make a sound like that. Also, check the back brakes, too. If the guide pins don't slide well you can wear out the inboard pad only.
Good luck with the problem, and check out realoem.com if you want to see part numbers and exploded diagrams of your car.

I have a similar issue when the car is cold, or when I take left turns hard. The way the suspension handles the load effects my noise. I found this tip from a thread here, maybe it can help you.

"There is also a bushing that limits travel on the steering rack. If that got deformed somehow, it would cause what you're describing."

http://www.318ti.org/forum/showthread.php?t=19161

Try shutting down the engine while rolling; it should help you narrow down where the noise is coming from (at the wheels or directly underneath). I hope I don't have to tell you that this will make braking and turning much more difficult, and to only turn the key back one click or the wheel will lock.

I would also try spinning the rear wheels. Based on the second description of the sound, it could be a stuck parking brake. It could make sense that if your parking brake is too tight, the rotors would shrink around the shoes to create constant contact.

I spun the rear wheels on some ice today to narrow the noise down. With the rear wheels spinning, the rotational noise is there, it sounds like its coming from the front, but it very well could be from behind the dash area or under the console. I have to check the heat shield next as per the previous suggestion.

Thanks!

You said you had the wheels off (I assume the car was on jack stands). Have you tried rotating the front and rear wheels then to see if you still hear that noise. If not, then it could be something rubbing since it only happens when the weight of the car is on the ground.

What if any was the outcome of this problem. I live in Fl and have the same model and mileage. The sound is as you described but with a cranking sound when turning only in first gear. Don't think it's brake related. Gonna look around before servicing so please let me know if you found the reason for the noise.