Driveline noise - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

AUII_Forte · 09-20-2002, 01:51

I noticed today that my car makes a very scary noise in the driveline at very low speeds i.e. <10km/h. I think its the diff, but not 100% sure. I don't think its the trans, its just had the S5 replaced and had a full service and the guy said it was in pretty good nick. The noise is a kind of clunking and its worse in reverse. Could the diff need oil in it? I hope it doesn't result in me having to replace the diff, coz I CAN'T afford it. :(

I thought it may be the uni's as there is a bit of a clunk between R and D that sounds like the uni's picking up slack. It's very difficult to pin point where the noise is comming from while sitting in the drivers seat, I haven't had the chance to get someone else to drive it so I can have a good listen and look. From what I can tell its comming from the back end of the car.

Any ideas and comments would be appreciated!!

old_mate · 09-20-2002, 04:02

Make sure your engine mounts have been tightened, I had a very similar problem with mine, and I could swear the knock was coming from the rear, but all it was was a loose engine mount bolt.

TopGhia · 09-23-2002, 00:38

Check and top up your auto fluid and diff oil, using the recommended stuff.

Does this noise occur on acceleration, deceleration or all the time. If you coast to rest in neutral, does it still occur then? Is there any sort of shudder?

AUII_Forte · 09-23-2002, 01:21

It happens at low speed only when the car is hot. The fluid is fine in the transmission. I topped the diff up as well with proper fluid. I has a shudder in it at times.

TopGhia · 09-23-2002, 10:00

This is my reasoning.

If it happens only when the car is hot it can't be the diff, cause the diff doesn't care how hot the motor is.

ditto for the u joints and driveshaft.

The only thing left is the transmission or the engine, which are very heat dependent.

Does the noise go away when its shifting up to 2nd?

Of course, I could be wrong - noises are hard to do over the net.

AUII_Forte · 09-23-2002, 15:53

It happens when the diff is hot. I.e after a highway run.

TopGhia · 09-26-2002, 03:07

Quote:

I thought it may be the uni's as there is a bit of a clunk between R and D that sounds like the uni's picking up slack.

I think this points to the auto transmission.

Anybody else got any theories?

WBT56 · 09-26-2002, 03:55

It sounds like the diff has excessive freeplay in hemisphere. Time for an overhaul. Noise worsens when hot, as oil thins.

TopGhia · 09-26-2002, 13:23

WBT56 is probably right, I thought it was a single "clunk" but on re-reading the post it was a "clunk,clunk, clunk". Diffs usually go "whir,whir,whir" or "grind, grind, grind", but I think there is room for a "clunk,clunk,clunk" in there somewhere.

Take it easy
Dave

Bass Crazy · 09-27-2002, 00:39

Is the car lowered?

After I lowered my car I had all sorts of problems with the unis (3 speed EA) and had to change them twice.

If the car has been lowered, check if the Yoke is hitting the floor.

Good Luck