vz thud sound when goin at walking pace, what is it?

[mattyr82]

got a vz wagon on duel fuel automatic exec, when ur stuck in traffic and stopped with ur foot on the brake and then u release the brake and start rolling at walking pace, it makes a thud sound as tho im running over those little square reflectors on the rd, it is constant until i start accelarating, it just goes thud,thud,thud like the kind of thing as if u had some rubber hanging off a tyre and smacking on the guard with each rotation.
it sounds like it is coming from the transmission.

 

[Big Red VF-SII Go-kart]

My VZ wagon also thuds briefly when starting off at slow pace. The Holden Service Manager, who I had spoken to on unrelated matters, is aware of it — so too, many other owners; IIRC, something to do with differential / axle and considered normal.

 

[noyzv8]

my vn commodore made a similar noise, turns out it was the tail shaft uni... just a thought.

 

[Not_An_Abba_Fan]

The IRS Commodores have a habit of wearing the diff mount bush, the diff clunks up and down when it is worn and it sounds like someone is under the car and thumps the floor.

 

[mattyr82]

The IRS Commodores have a habit of wearing the diff mount bush, the diff clunks up and down when it is worn and it sounds like someone is under the car and thumps the floor.

thanx mate, i hear that noise u descibed but it comes from under the console area betwwen the front seats, is that where i should hear it, or from the back, sounds can be hard to pinpoint i suppose.
popped my head under, and are u talking about the big "u" shaped thing on the rear of the diff housing? is the bush easy to change?
also the rear wheels are wearing on the outside.

 

[Big Red VF-SII Go-kart]

The thud comes from the rear.
To say it comes from the console up the front is truly alarming. Just what is it that is going thud under there??

Visible wear on the outside of the rear wheels is an alignment problem (unless you're running donuts on only two side wheels!?). Camber is out (wheels pointing out rather than in). I think thrust alignment corrects out-of-line camber. It would have to be a pretty marked misalignment for wear to be visible.