This is a copy of emails I've sent to people who were having diff troubles, the problem should be made as public as possible, because a Holden workshop mechanic said that he has had a few customer pay for the complete rebuild of their diffs, when they only needed to have the inner shafts Loctited back in a 1.8hr job done with diff in car.

Hi, noticed your post in just for Comodores forum, this problem you have is big, and may be an even bigger cover-up by Holden, this "attached" document is a "for your eyes only" document sent to all service managers and to me by an inside friend at GM Victoria who will remain anonymous.
I was told I needed a complete diff rebuild by two Holden service managers to cure my cyclic knock problem only 1 month ago, and I have exactly this problem, and I know that all service managers received this document years ago early 2005. So I was going to get charged nearly $1,000.00 for the rebuild and all they were going to do is what was on the document, 1.8hrs and free inner shafts/circlips from Dana if still under warranty.
Everyone should make this as public as possible.

http://forums.justcommodores.com.au/vz-hol...gm-coverup.html

Cheers George

I am familiar with this Techline.
When I worked for a Holden Dealership we performed many of the procedure.
The 'Cyclic Knock' is produced by freeplay in the driveshaft to diff spline mating.
If the above is true then the Dealer is not up to date with Holden info or possibly a little "dodgy".
I certainly wouldn't stress, in general, about this one guys.

I have seen this too and on my vz. The dearler picked it up and just repaired the unit for me.

From my experience, you were very lucky, as I said I had 2 Service Managers from different dealerships but affiliated by the one owner, they both took mine for a drive, and both said I needed a $1000 diff overhaul, then thankfully I came upon this tech report and fixed it myself with out even renewing the upspec inner shafts, (Too expensive @ almost $400 for the pair). Just new $1 circlips and Loctite them in and all is fixed for $2 and 2hrs of my time. I pity all the customers they said they did before mine, who got charged the $1000 overhaul for nothing.


Cheers George

Hey George

Any chance of emailing me that doc?? I dont have enuf posts to access on JC... vinnycolouda@hotmail.com

Cheers

vin

Hey George, could i please get a copy of that letter too please? i dont have enough posts to view too

jwhart@iinet.net.au

THANK YOU!

Jared

http://forums.justcommodores.com.au/vz-hol...gm-coverup.html

I was unable to obtain the document, I too would appreciate an email copy. I have a VY commodore with diff backlash, and have been told by my holden dealer that I need the $1000 diff replacement/rebuild

George

Can you send me a copy of the document on the Diff problems

my clubsport has just started making the noise only has 35K on it

Grant Stevens: gstevens@maxbryant.com.au

Hi George,

I know this was posted a while ago but if you are still following this discussion could you please send me this info as well. I hav an 05 SV6 that is making this knocking noise and being a fitter by trade I know that it is gear backlash. I would just like to have some proof of an inherant problem before I take it to holden. Any chance you could send me the dac as i have just joined just commodores and dont have access to the doc.

my email address is bardo24169@hotmail.com.

Thanks mate..

Hi George,

I recently bought a commodore VX S 2001 and have realised that there is a diff backlash. this has also been identified by the mechanic from Ultra tune. i got a major servicing done from Preston Motors (Authorised Holden dealer), they didn't even bothered saying anything about it.
can I please get a copy of the mail so that I can get back to Preston Motors.
they have already charged me $480 and nothing has changed yet..
please mail me at pholit@hotmail.com. I'm not able to access the post in just commodore as I'm a new member.
thanks George

Hi Brado,

I have just come across the same diff backlash problem and Ultra tune said would have to spend more than $1000 to fix it. can you please forward me the mail if you have received it by any chance.
Mine is a Commodore VX S 2001

please mail me at pholit@hotmail.com

thanks Brado

Watch out that your all on the same topic.
The old Holden issue was a cyclic knock involving the axle shafts being glued into place....as a first attempt fix.
There is also the Limited Slip Diff. grinding noises on tight, low speed turns. An additive was introduced to the diff. oil to fix.
Diff backlash is normal. All diff. gears have gear backlash. Sometimes you hear this when the trans changes gears? Or when you apply the throttle on take off?
If this is so reduce your level of concern. "a vehicle characteristic" we used to say.
Becomes louder with age AND once you hear it, you can't get it out of your head.
It's the result of freeplay accross several components in the drive train all being taken up at once "thump!"
If the diff was rebuilt the backlash could be reduced, perhaps, or it could end up worse.

Hi George

If you're still following this forum is there any chance you could email the document also. My 2002 VY Commodore Station Wagon has diff backlash also and I'd be keen to explore all the possibilities before I get it fixed.

Thanks
Luke

luke.a.conroy@gmail.com