Noisy diff

[Clubby82]

The diff on my vy clubsport r8 is really noisy and makes a lot of clunking sounds. I can hear it especially at low speeds and when cornering. Sounds like something is grinding. The car had done 103000 k's. Asked Holden about it and was told the noise is common for that model and they made it looser to handle the power. Was told they can put a 'chatter' kit on which takes around 1500-2000 k's to start working and reducing the sound. What is the best solution and is this problem common? Do I need to get a new diff or does it just need to be serviced? And what about costs?

[Vt_vic]

mine used to do it but not as bad had it serviced and its much better

[Sean880]

The solution depends on the problem and in this case I believe ideally the diff needs to be removed and inspected.

The most common cause of the kinds of problems you have described is abusive driving and resultant abnormal wear to the diff. " Healthy" LSDs used by Holden in the VYs don't make noise. Worn and damaged ones do.

As a first step I would check the fluid level in the diff and also check for leaks. I would then change the diff fluid and change it a second time after 500 kms or so of driving. When you do the initial change look for small metal particles. If you find them there is certainly deterioration to the diff. Use either Penrite SIN Gear Oil 80 - a fully synthetic 80W-140 grade diff oil or Castrol SAF-XA, also a fully synthetic 80W-140 grade diff oil . These are the only diff oils these 2 companies each recommend for the Commodore VY LSDs (and I checked it out personally with them recently). These oils have the required additive in them. (So don't use diff additive with these fluids).

Maybe a flush and fresh fluid will make a difference but quite possible not especially if there really is damage/abnormal wear to the diff. However as an initial step it is not costly. If the noise persists just the same, I would be having a specialist who is familiar with Commodore LSDs inspect the diff and give you advice on your best options. It won't be cheap though.