Adventra - clunk after driving a several metres forward

[try_again]

Hello,

VZ V6 Adventra makes a single clunk noise after driving forward for several metres, but only after reversing and only if the car had been sitting for a long time (i.e. overnight).
The sound appears to be coming from the front drivers side wheel area. Makes no difference if the wheels are straight or turned.

I considered a loose brake calliper housing dragging back and then forward on the disc, but that seems quite OK on inspection.

Thoughts keep drifting to drive line components, but I'm thinking that would make noise on change of direction, not several metres down the road.

The noise has been happening without fail for a week now, but I haven't been able to replicate it after it happens unless the car has lengthy rest.
... I just had a thought - I need to confirm that reversing sets this off; I'll reverse all the way down the drive way, then drive forward to the start of the drive way; the next morning the car can then be tested forward.

Cheers

 

[try_again]

Follow up: It seems to be happening at the change from 1st to 2nd, but it's not like it's 'clunking' into gear; the gear change itself seems OK, is there something else that happens at the same time (inside the transmission?) that this could be?

P.S. the noise is happening more often now.

 

[SuckSqueezeBangBlow]

Does it only do it once? If so, it could be ABS self check?

 

[try_again]

Does it only do it once? If so, it could be ABS self check?

It will do it once per driving event from cold, then only again after it's been sitting for a few hours. i.e. if it's driven after a shorter rest it won't clunk.

 

[Towcar]

loose drive shaft or half shaft bolts maybe.

 

[try_again]

Thanks for the suggestions so far; here's the latest:

- It's now clunking without the cool down period, but not quite every time.
- it always happens at 10 km/h regardless of throttle
- it only happens driving forward after the car has just been started, it doesn't happen if starting from stand still if the car is still running.
- will still do it if having reversed just prior.
- clunk If A/C turned on or off
- clunk if Stability control turned on or off
- clunk if A/S on 1st gear selected, or auto
- clunk used brakes prior or not

I would some more info on the ABS ( self check, as suggested by SSBB) and all wheel drive system - do these symptoms fit?

 

[figjam]

My Monaro always 'kerchunks' like that when cold, reverse out of garage, drive forward 5 metres ....... kerchunk ...... seems to me to come from around the passengers footwell. Told that is the traction control kicking in. Still there after 14 years.
My Cross6 doesn't make any noises like that.

 

[SuckSqueezeBangBlow]

The ABS self check was most noticeable on my BF xr6t and since then I've heard it on probably every car I've driven which has ABS.

 

[try_again]

The ABS self check was most noticeable on my BF xr6t and since then I've heard it on probably every car I've driven which has ABS.

Thanks for the vid, the noise is not too dissimilar. It may very well be a normal function of the vehicle but my concern is that for the first 11 and bit years of its life the clunk wasn't there, or at least not as noticeable as it is now.

A new symptom to add to the list is that the clunk can now be felt through the accelerator pedal... if this rate of change keeps up something will stop working soon - then we'll know what it is!

 

[uniacidz]

Could be a lot of things

Loose bolt or nut and when moving forward, places pressure onto the area and hence get the clunk

Had car serviced recently?

I had a clunk under braking, ended up that Pedders did not tighten a lower control arm bolt and was round 20nm and supposed to be 100nm
Got worse over time

Over a year or so period was noticeable more and investigated myself and found the cause .
Confident to get under the car with a torque wrench and start tightening things?

Common failures are of parts for age of car.
Sway bar link pins
Sway bar D-Bush
Shocks and top bearings
Lower control arm bushes
Radius rod bushes

Whatever service history like?
Changed any suspension parts?

Go to a Pedders and do one of those cheap reports and then freak out about the price they charge then do yourself