weird sounds when i reverse....

[Irukandji]

Hey just got a quick question.

When i reverse for about 10 seconds...i hear a very weird grinding sound. It goes away after a couple seconds but comes back now and then. I have no idea what it is. The grinding sounds are coming from teh back of the car. Anyone know whats going on? It only makes sounds in reverse or when im backing down my hill in neutral.

:x:

[TheSnail]

3 possible things

-Drive shaft
-Diff
-Rear brakes

My guess is the brakes.

[Irukandji]

3 possible things

-Drive shaft
-Diff
-Rear brakes

My guess is the brakes.


Hmm...the rear brakes ...thats a possiblilty. before i bought the car, my mechanic said they were in bad condition (the rotors mainly)....so i got new rotors and new brake pads. Maybe something went wrong while resurfacing the rotors? :bash:

[brianglawson]

mine does that too, except it also pops and rattles, new rear brake rotors, pads and lines, new differential, new suspension, i dont know what the hell is causing mine, unless its the old calipers in the back???

[mellojoe]

Well, you have to remember that the 240 uses disc brakes. Disc brakes use pistons to CLAMP the pads to the rotor, but they don't really do anything to push the pads back AWAY from the rotor. When the fluid leaves the brake cylinder, the pistons are allowed to float back.

if you use the parking brake (like most of us do) when you park, you squeeze the rear pads together. Then, when you back up, those pads will rub a little before completely releasing the rotor.

Why does it make a noise in reverse only? I think it has something to do with the grooves we wear into the pads. By moving the rotor in reverse, you are moving the pad slightly out of its normal path of operation. There might be a slight rut there, and as the pads cross this "rut" it makes a humming noise.

Maybe?

[Pepperoni]

I had a grinding noise. I had an open diff, put in a vlsd, and i have not had that grinding sound ever since.

[Munch]

just thought ide put my two cents.

ive had this same problem for awhile now. i was gonna replace the gear oil in the diff and tranny cause i thought that would alleviate the problem, but i still havta get around to that.

anyways, so my car was making that grinding noise in the back while reversing, but then the other day i put some air in all my tires cause they were pretty low and i since then i havent heard and grinding while reversing.

[brokenben]

air in the tires? hmm..

well.. i have that same problem.. only in reverse.. let me know if anybody knows for sure what causes it.

[revat619]

I had a grinding noise. I had an open diff, put in a vlsd, and i have not had that grinding sound ever since.

Same thing on my car.

It used to make this loud grinding noise and it only happened in reverse, not all the time but occasionally. It happended even more so on cold days. Anyway, got rid of the open diff and got a vlsd. I havent heard the sound since. Btw, i've had the vlsd in for atleast 4 months now.

Moral of the story, its probably your diff.