Noises...no idea where they're from...

[Sean]

Alllrighty. So, I did some searching, and have made some of my own conclusions, but want some others ideas as well to see if I'm right.

Noise #1:

Ok, so this is actually very very annoying. My car is already decently loud with my exhaust, but the whining that occurs makes it very difficult to talk in my car. I always hear it unless I have my music pretty loud. The noise begins as soon as I start moving forward and continues...well forever. 100+ mph. Gets louder the faster I go. NO VIBRATIONS at all. It's definitely coming from the rear, but what side, I have no idea. Driving next to cars with my windows down, I hear a bunch of whining coming from my car. At slower speeds, I hear squeaking that goes (squeak....squeak...squeak - stops above around 25 mph). I've felt my rear hubs, and neither one feels abnormally warm. about 245,000 miles on original bearings, from my records. Diff fluid is Redline with maybe 20-30k on the fluid, about 200k on diff. noise DOES NOT subside when I push in the clutch and remove all load from driveline

I think it's both rear bearings...I can't figure out which one. Opinions on this? How can I figure out if it's one or the other or both?


Noise #2:

This one is REALLY weird. And, I cannot, for the life of me, figure out what would cause it. A long time ago, I started hearing a very subtle "click or clunk" noise from my rear brakes. if I was going in reverse, and tapped my brakes to stop, I'd hear this very short subtle click noise. It kinda sounds like there's a 1in gap between the pads and rotors and then the pads SLAP the rotor - *just a way to describe the noise...there is NO give at all, that I can feel" Well, recently it's started occuring when I get up to a stop sign when moving forward, and I hear the clicking noise right before I come to a stop. It's getting louder in reverse too. When I want to recreate the noise, I can't. I thought maybe it was my ebrake boots, so I tightened up the cables, and it still occurs.

I haven't removed the calipers yet to see if there's somethin up. Could my pins be gummed up? Ideas here?


Other than those two weird things, car is running like a champ. Except for the mess the whole underbelly of my car has from some stupid tiny oil leak (or some other fluid - no idea what) and my custom exhaust's poor alignment with my rear valance bugging me - no issues! :)

Sorry it was so long. Ok, thanks in advance!

-Sean

[HST]

#1 could be a loud diff. They can make a high pitch whining sound, changing the fluid might help, but probably not much. If it sounds like it is coming from the center of the car it is probably the diff. Sit in the back while someone else drive the car to listen better.

[Sean]

#1 could be a loud diff. They can make a high pitch whining sound, changing the fluid might help, but probably not much. If it sounds like it is coming from the center of the car it is probably the diff. Sit in the back while someone else drive the car to listen better.

Probably a good idea. I might pull off the seat too...just thought of that.

[lordofthewaters]

Could be the fuel pump. Mine does something similar to that. Gets louder under acceleration.

[Sean]

Could be the fuel pump. Mine does something similar to that. Gets louder under acceleration.

Nah, it's not fuel...doesn't change with Revs, changes with speed...definitely not fuel pump.

[AlarmedBread]

Kind of a toss up on the bearing/diff noise, sometimes they make loud grinding sounds when they're done for.

Have you done all your rear sub frame bushings?

Get that thing ready for spring, mine will be! :mrgreen:

[ethree]

Noise #2:

This one is REALLY weird. And, I cannot, for the life of me, figure out what would cause it. A long time ago, I started hearing a very subtle "click or clunk" noise from my rear brakes. if I was going in reverse, and tapped my brakes to stop, I'd hear this very short subtle click noise. It kinda sounds like there's a 1in gap between the pads and rotors and then the pads SLAP the rotor - *just a way to describe the noise...there is NO give at all, that I can feel" Well, recently it's started occuring when I get up to a stop sign when moving forward, and I hear the clicking noise right before I come to a stop. It's getting louder in reverse too. When I want to recreate the noise, I can't. I thought maybe it was my ebrake boots, so I tightened up the cables, and it still occurs.

I haven't removed the calipers yet to see if there's somethin up. Could my pins be gummed up? Ideas here?

Is the noise noticable if your'e coasting at lower speeds? I have a simalr noise, more of a clunk than a click but definitly in between the two, I notice most frequently when coasting to a stop.

[Sean]

Is the noise noticable if your'e coasting at lower speeds? I have a simalr noise, more of a clunk than a click but definitly in between the two, I notice most frequently when coasting to a stop.

Coasting with the brakes, not until I come to a complete stop though.


Oh, and Chris, yes...all bushings are solid. And by solid, I mean newER - less than 40,000 mi on the whole lot...if not around 25,000. All polyurethane. Definitely not the problem there. :)

Oh, and it's always nice here in Indio, CA. Was like 75 today. I'm driving home to Idaho in 2.5 weeks though, so just thinkin about trying to fix this first...maybe. I know I'll make it home fine though. Just that I'll be driving to East Peoria, IL following that. hehe

[emi325i]

#2 could be subframe bushings

[AlarmedBread]

Might sound dumb, but check the torque on your brake caliper brackets. Very similar symptoms on an e36 who lost a bolt and the rest were pretty loose after a recent brake pad change.

[Sean]

Might sound dumb, but check the torque on your brake caliper brackets. Very similar symptoms on an e36 who lost a bolt and the rest were pretty loose after a recent brake pad change.

Yea, I need to pull off my tires and see what my brakes look like.

#2 could be subframe bushings

Shoulda read my post above, all my bushings on my car are less than 2 years old and all polyurethane.

[redhatpat]

Shoulda read my post above, all my bushings on my car are less than 2 years old and all polyurethane.

And new parts never fail? If you're going to make these assumptions, don't bother fixing the car, just drive it until something breaks.

[delatlanta1281]

ok the first one is your diff or the dentist in your rear speakers.
Second could be loose lugs? I had that happen. I know I know, just chek them.

[Sean]

Took out my seat, and I could definitely hear the noise better - it's the diff alright. It changes pitch as I release and engage the clutch.

So, if my diff is making all that noise, is it literally on its way out, or would a fluid change fix it? If I have to change it...that sucks. Its impossible to get those mounting bolts off! What does everyone else to to get them off?


Didn't have a chance to check my brakes, but I just remembered I had to pull my subframe in June, and my bushings looked perfect, so that's most likely not it.

[zaust]

If it's the diff it will need a rebuild. But also check that the drive shafts (the splined end that goes into the diff) Has plenty of grease on them. When they are dry they cause a whine too...
Drop the whole rear sub frame. It is much easier to do when it's all on the floor.