So I've had a clunking noise for the past thousand kays. However recently it's been getting pretty bad. Have already replaced the gearbox mount and propshaft, and recently just spent a heap on having all the subframe and diff mounting bushes replaced. Still hasn't fixed my issue however. Now I'm thinking it has to be either my diff or *gulp* gearbox itself. What would be the telling signs of either? And what possible damage could I do if I continue driving the car like it is? Thanks in advance
Sorry, should've been more specific. When changing gears it can be heard, along with whenever you take your foot off the accelerator. Then when you put your foot down again you can hear it clunk (sounds like it's coming from the rear) and feel a jolt through the car as if the drivetrain is getting a sudden load on it?
mine does the exact same thing.. i got told by joe at dontek it was my diff bushes,, getting them replaced soon will let you know the outcome
Sounds like too much slop/backlash in the diff. You can check by jacking the rear up, put car in neutral, get underneath and start turning the propshaft backwards and forwards. You will see if the wheels turn when you rotate the shaft or if there is a lot of slop there.
@TeeJay, even with subtle throttle you can notice that it's there you just don't feel it as much. Stef, how much backlash should our cars have? And if this is the issue what should I be doing to look at getting this fixed?
It sounds like diff backlash like stef said, its basically where the gears in the diff have the tiniest bit of play and are not meshing perfectly smoothly. You either get it corrected (rebuild diff) or put up with it. When i shimmed my old diff i got backlash, and drove/drifted like that for 6 months no issues.
Your diff does have a small amount of backlash, nothing out of the ordinary. I would replace the rear shocks first, we know one is leaking. Clunking shocks will usually show up on bumps as well as on/off throttle situations.
Backlash is a rather ugly feel when trying to get a smooth feel from your vehicle. My Zed has a little, and my turbo ute has a lot. Maybe ~15-20 degrees of rotation on the drive shaft before anything happens at the wheels. Will be fixing it asap. Its annoying as feck. As drz400y said, a leaking shock will create a knocking/clunking sound too, however i wouldnt have imagined it would be as noticed through the drive train unlike a sloppy diff. Keep at it though, sounds like you're nearly at the end of the important replacements. New bushes are a big thing to have these days. GL.
Before you spend money on all the previously mentioned diff, shocks, mounts etc I suggest you get it up on a hoist and have a good look underneath to make sure it's not something simple like exhaust knocking against the body or the gearbox. When you alternate between drive and over-run the GB can move a bit, even with good mounts in place, and if the clearances are small then parts will knock together and can sound worse inside the car.
