"Clunk" upon launch

[VzVzVz]

Whenever I release the clutch to move off in my ute, there is a clunk from the underside of the car. Same when I deccelerate without braking in 1st.

I'm thinking it might be a uni joint or diff gears taking up, but it sounds (and feels) too strong to be anything normal. Is it normal? Does anyone else's VZ do the same?

[Veriton]

Had the same thing on a camry, turned out to be torsion bar nut was about 3 threads from coming right off (which isn't a pretty thing when it happens), It'll be something similar I'm thinking as commodores don't have torsion bars I think.

[PRAVX II S]

Could be engine mounts and could be other stuff to mate. You will have to check it out or take it somewere to get it looked at

[torana355]

It would be the diff taking up. Mine is loud as hell.

[andyman]

is it a lsd? aswell, sounds like diff backlash, holden lsds are real clunky at low speeds too

[VzVzVz]

is it a lsd? aswell, sounds like diff backlash, holden lsds are real clunky at low speeds too

Would a LSD make that kind of noise? Because it definately sounds as if its coming from the rear end.

[VzVzVz]

Just doing my diesel technician apprenticeship and studying diffs. It seems if it makes that noise, the diff gears are worn.

I would really like some feed back on how common the problem is. The car has got 130k on the clock and has don mainly long hauls across the country. Could this add to the problem?

[torana355]

Just doing my diesel technician apprenticeship and studying diffs. It seems if it makes that noise, the diff gears are worn.

I would really like some feed back on how common the problem is. The car has got 130k on the clock and has don mainly long hauls across the country. Could this add to the problem?

lol, mate stop worrying. The diff gears will not be worn, but the shims that are used to adjust the backlash may need adjusting. Holden use really crappy diffs and they all clunk to a certain extent which if within the specs is normal!!. Mine is really bad and happens all the time at low speed. I could get the diff adjusted/ rebuilt but it will not take long to start clunking again.

[andyman]

essentially if you have a lil slop between the cv shafts the diff tail shaft, because of the nature of an lsd 'locking up' so to speak in a straight line, as you start to turn it will slightly wind up untill the cone slips (commodore lsd is a poorly designed cone clutch) once the cones break so to speak and slip, once that sort of wind up releases you get a slight knock,

that noise will only happe on slight turns, and youll only really notice it at really slow speeds,

clunks on take off could be pinion backlash, cv joint play