Adventra Diff Rattle

[SteveSX6]

Hi guys,
I've got a 2006 VZ Adventra with what sounds like a rattle in the diff.
The cars done 140k which puts it outside of Holdens warranty period.
The rattle comes in on slight overrun, such as when you are coasting down from around 100km and comes on pretty strong around 20-30km,
It disappears if you shift the transmission in to neutral, or downshift, or accelerate slightly.
The noise is constant regardless of whether the vehicle is travelling in a straight line or cornering which to some extent rules out the cyclic know issue that these diffs are known for - the Holden service bulletin specifically lists slaloming the vehicle whereby the noise should disappear or reduce if it is the cyclic knock - this noise remains
Best description of the noise I can come up with is as if there is something loose rattling in the diff housing. The noise can also be felt through the vehicle.
The noise is speed related and slows as the vehicle slows.
The local mechanic has been through the more obvious possibilities and checked wheel bearings, inner and outer cvs, universal joints, diff mounts, tyres.
They have also had the back off the diff to ensure that there was nothing there that shouldn't have been.
They did however find brass or bronze fillings in the bottom of the diff housing.

Do these diffs have a set of shim washers that could have worn allowing some float in the diff?
Any other suggestions would be welcome as I am scratching my head on this one.

Cheers

Steve

 

[andyman]

is it lsd rear?

does the lsd still function correctly?

if its brass or copper, could be a clutch that has fallen away or fractured, possibly could have gotten drit in the bearings scoring the bearing surfaces, possiblles anyway

 

[SteveSX6]

Thanks Andy,

As far as I can tell the lsd is still active and functioning correctly,
It still binds up in a tight corner if you encourage it somewhat. Its not a particularly aggressive lsd though.

A fractured clutch is not something I had actually considered.
If one of the clutch packs has a fractured plate that could explain the rattle.
I suppose the only way to determine that is diff out and strip it...

I had the diff oil changed at the same time as the other work above was done and although it was dirty there wasn't any evidence of serious wear, in terms of bits floating in the oil - it suggested it hadn't been changed for some time.