Clunking (serious please)

[Blizzard96]

I have a 1996 A4, sometimes when it shifts, it will make a sort of clunking noise and it doesn't feel firm. I rode in my friends 2000 Mustang, and his only does it when you brake hard from going fast (like having to stop at a red light after doing 40+). Any ideas?
My car is still under warranty, but I'd like to know what to tell the dealership what to look for. Thanks.

[Fin]

Can you be a little more specific about the 'clunking'? My '94 3.4L A4 Camaro would 'clunk' on downshifts going between 2-1 sometimes, and also sometimes when I would hit the gas in just the right gear. This is somewhat normal for GM 10-bolts, although if you think it's really bad, you should probably have it looked at. If you haven't had the fluid changed in awhile, I'd suggest getting that done, too.

[Blizzard96]

I've had the transmission fluid changed more than twice in the last year (probably more). Gaskets and filters too...

Basically, when it shifts its supposed to feel smooth right and you don't hear any noises. Sometimes if I have to stop from a high speed (exiting the freeway/red light) its as though I can hear something hitting something else and can feel something. Or after I get off the freeway driving home and hit the residential area when it shifts, I'll hear that noise. Right when it shifts, it clunks. Its a low toned "thud" almost.

[SuprSpdDB7]

it's your rear axle going to break loose!!!

no... just kidding... :D

TTT

cause i would like to know too!!!!

[Fin]

Is the sound coming from the rear of the car, or where? I was referring to the rear-end & getting it serviced, not the transmission.

[Blizzard96]

Yeah, I guess the rear...defin. not the engine...sounds maybe around the drivers seat and behind.

I just had the diff. filled, don't know if they changed it though.

[1998silverbird]

I think it is your rear end. my car does that sometimes too.

[strange_trp]

check trans mount just to rule this out. in park, put foot on brake pedal, apply parking brake. put trans in drive and with your foot still on the brake floor the accelerator for like 1 second. make sure nobody is near the car so you dont kill them. listen for clunking noise. do the same thing in reverse. go back and forth a few times listening for the noise. do not hold the accelerator down with the trans in drive and the brakes applied (aka stall testing... useful for trans diagnosis but not also not really good for trans). if you hear the same clunking noise going from R to D and when you hit the gas while holding the brakes, visually inspect and replace trans mount. based on your description it doesn't sound like this is the problem but its worth testing first.

shake down exhaust system to rule out contact between exh and underbody. also check exh mounts. again, just to rule out.

it really kind of sounds like a differential problem based on the limited info provided, maybe a bit too much backlash in the ring/pinion... "clunking" noises are difficult to diagnose online because i really can't hear the noise myself or (more precisely) experience the noise...

rule out trans mount and exhaust hitting underbody just to make sure... anything else you can think of to help with diagnosis???

edit: also check universal joints... grab driveshaft and firmly move in and out, up and down, looking for any movement in u-joints.

[ June 21, 2002: Message edited by: strange_trp ]</p>

[DominusEtDeusNatus]

Sounds like ABS. Mine does that if I break really hard in the rain. I was told a while back it's supposed to make this noise. Sounds like a 100 midgets beating each other with steel pipes under there.

[Guardsman]

If you get under the car when it's not running, and grab the drive shaft, it's got a bit of play, so it can rotate just a little bit. When you're driving, and on the gas, all that play is taken up, and everything is tight. When you let off of the gas, the driveshaft goes loose, and the play is there again. Then, when you hit the gas again, the driveshaft has no load on it for a fraction of a second until the play is taken up, and that's what you might be hearing.
Put you car in neutral, set the parking brake, and then grab the drive shaft and turn it as hard as you can, and see if the sound is the same as what you're hearing.

[Blizzard96]

Thanks guys, I'll try all your suggestions this weekend and check back afterwards...

I appreciate all your help. [img]smile.gif[/img]

I've felt it in my friend's 2001 Mustang when he is going fast and then has to stop quickly (at a red light). Feels like when it downshifts something hits...it makes the thud noise and you can sort of feel a soft hit.

So if anyone has had a brake hard in their automatic and have heard a noise and felt a small jolt...thats probably what I'm experiancing.

[ June 21, 2002: Message edited by: Blizzard96 ]</p>

[Arctic02]

My trans. mount got insanely loose and actually lost one of the bolts holding it to the trans., does anybody know the specs. for that bolt, i.e 13mm, course? fine? length? That kind-of stuff? It clunked real bad from the floor board.

[strange_trp]

<blockquote>quote:</font><hr>Originally posted by Arctic02:
My trans. mount got insanely loose and actually lost one of the bolts holding it to the trans., does anybody know the specs. for that bolt, i.e 13mm, course? fine? length? That kind-of stuff? It clunked real bad from the floor board.<hr></blockquote>

dealer parts dept should be able to tell you.

[Arctic02]

The guy at the counter really tried, but he couldn't get the bolt on the computer.

[xdamxincx]

U joints