Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

clunking noise from the rear of the car

stocky

New Member
Joined
Jun 14, 2005
Messages
5,040
Reaction score
80
Points
0
Age
36
Location
Melbourne
Members Ride
1995 HSV Clubsport T5, 1991 VN Berlina
just noticed something different with my car lately.
if i am travelling, say, above 50 and i let it idle at that speed for a while for a while, when i press the accelerator i get a bit of a clunking noise from the rear. its makes one noise and then its fine. sounds like its from the diff.
is this normal, or could something be wrong?
 

Morton

For external use only
Joined
May 20, 2006
Messages
4,097
Reaction score
84
Points
0
Age
36
Location
Melbourne
Members Ride
Fairstar the Funship
My old diff did that, when it had a busted centre bearing, cracked panhard bar rubbers, cracked upper and lower control arm bushes and rooted diff bushes. After I replaced them all and fitted a vs diff and lower arms, the clunking was fixed. I suspect it was the centre bearing that caused the clunk, but it could be a sign the diff is on the way out. If you get lucky, you can score a new one fairly cheaply. I got my vs diff fitted for $150 with the lower control arms.
 

pandaman

Aussie Muscle Fan
Joined
Feb 13, 2006
Messages
783
Reaction score
24
Points
0
Age
38
Members Ride
VN Berlina 5.0 A4
Sounds like backlash, it happens when your driveline starts getting old and you start getting play between components. Or it could just be rooted bushes, easiest thing to check would be to look at the rear suspension bushes make sure they're intact, if so then theres probably some backlash in the diff.
 

savage1987

Donating Member
Joined
May 8, 2005
Messages
3,660
Reaction score
31
Points
48
Location
Townsville
Website
www.facebook.com
Members Ride
LS1 VN + WK Grange 0010 + HPW VX SS
Cheers guys. I was having the same trouble, just wasn't too sure how to explain it lol. What diff options do I have? I'm looking for LSD . . . any bolt-overs from other models? Is there much modification of rear suspension required?

And I don't really want to change the ratios too much, if I can help it . . . heaps of highway driving . . .

Cheers
Sammy B
 

bradcad

New Member
Joined
Jul 28, 2006
Messages
505
Reaction score
6
Points
0
Members Ride
VT Berlina & mazda 2 DE
i'm having similar noises, however i also seem to have a bit of 'wobble' in the ass end when coming to a full stop. Anything harder than a gentle stop and you can feel the back bouncing before coming to a stop.

yes shocks are new...
 

pandaman

Aussie Muscle Fan
Joined
Feb 13, 2006
Messages
783
Reaction score
24
Points
0
Age
38
Members Ride
VN Berlina 5.0 A4
savage1987 said:
Cheers guys. I was having the same trouble, just wasn't too sure how to explain it lol. What diff options do I have? I'm looking for LSD . . . any bolt-overs from other models? Is there much modification of rear suspension required?

And I don't really want to change the ratios too much, if I can help it . . . heaps of highway driving . . .

Cheers
Sammy B

An LSD diff from any VN sedan or live axle VP sedan will definitely fit. Other than that, Diff centres from VN/VP wagons and utes will also fit, but not too sure about the whole unit, theres probably a thread on it around here somewhere. Just do a search for LSD in the VN section, should turn something up.
 

Stevob

New Member
Joined
Jan 22, 2006
Messages
48
Reaction score
1
Points
0
Age
54
Members Ride
May 1991 VN Wagon V6 Auto
bradcad said:
i'm having similar noises, however i also seem to have a bit of 'wobble' in the ass end when coming to a full stop. Anything harder than a gentle stop and you can feel the back bouncing before coming to a stop.

yes shocks are new...
You've got some worn bushes in your rear suspension. Possibly panhard rod bushes.
 

Immortality

Can't live without smoky bacon!
Staff member
Joined
Apr 15, 2006
Messages
22,480
Reaction score
19,936
Points
113
Location
Sth Auck, NZ
Members Ride
HSV VS Senator, VX Calais II L67
clunk when accelerating after coasting could be a badly worn universal in drive shaft, easily diagnosed by jacking up the car and manipulating the driveshaft by hand. any visible movement means it's shagged. otherwise bushes or to much play in the old diff. if your gonna get an LSD fitted, they should be able to sort that when they fit the LSD center and re-shim to set the crown to pinion back lash.
 

Benji

Vote For Pedro
Joined
Aug 14, 2005
Messages
345
Reaction score
14
Points
0
Age
34
Location
Central Coast
Members Ride
Looking For A VR - VS Stato V8
yeah uni joint or centre bearing is what id be putting my money on
My car does the same thing and its the centre bearing

Cheers Benji
 
Top