What's with these bloody Holden dealers putting an "additive" in everything to try and fix it?
Power stering shudder? Chuck in some additive!
Diff clunk? Chuck in some additive!
It's an absolute C.O.S and a cop-out if you ask me!
I'm lucky I haven't had the power steering problem, and when my diff started making noise, I demanded and got a new one under warranty.
...Additive...pfft...