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Hi, I am interested in peoples opinion on this very loud noise my na6 is making. It also started jumping out of gear as I nursed it home. Just want some opinions before I purchase a replacement diff for it.

It could be a loose heat shield, really hard to tell from that video, if you clutch in and let it idle, does the noise match the engine revs of the car's speed?

Popping out of gear makes me think it's either gearbox or clutch related.

Sorry, it wasnt popping out of gear, probably explained it wrong. It would stay in gear but all of a sudden would act like it was in neutral, so I would change down gears and it would engage again until it happened again. The noise corresponds with the speed of the wheels, whether clutch is in or not. If I drive slow the clunking is slow, if I drive fast the clunking is fast. If the wheels stop turning the noise stops. It is so loud and seems to be something major and internal.

Sorry can't be more help, only ever broke one diff and that was in the GC8, it died about 50 metres from work and we swapped in another in the work carpark so didnt really drive much with it broken to hear what it sounded like.

Sounds like the diff to me, although you've still got some drive in it. Although on second thought, a broken dif should not make this noise if the clutch is out and gear in neutral. I think. You should be able to confirm by jacking up the rear of the car and turning the wheels to pinpoint the noise.

Guran wrote:Sounds like the diff to me, although you've still got some drive in it. Although on second thought, a broken dif should not make this noise if the clutch is out and gear in neutral. I think. You should be able to confirm by jacking up the rear of the car and turning the wheels to pinpoint the noise.

... and if it's still not clear after that then disconnect the prop shaft at the front of the diff and try turning the pinion. You could check the rear drive shafts and hubs for noises too.

If it were closer I could loan you a diff to try/buy.

Ok thanks guys, ill let you know how I go

Ok, after doing a bit more research I find this on youtube, sounds exactly like my problem and they are saying its due to an "unbalanced drive shaft"




If this is right how can it be fixed?

Also after having another look under the car today, I noticed where the shafts join the diff they are uneven (see pics), could this be part of the problem? Just trying to determine exactly whats wrong before I go spending money on a replacement diff.



Cheers.

Really hard to tell from the pics but it looks like the diff oil seals are being pushed out. Right behind those are the main diff bearings ...

Pretty sure you aren't supposed to have what looks like an inch of the half shaft end hanging out.

With the pictures I would say that the driveshaft where you can see a lot of shiny chrome is probably due to the Circlip holding the stub axle in the diff has either worn out and broken off or the wheel has had a hit etc and it has pulled so hard the circlip has pulled through the splines.

I would think more than likely the spring has lost tension and can no longer hold the stub in place. Pull it out and replace the circlip and I think your problem will be solved. The shaft at the moment is just flopping around in there and is more than likely the cause of your noise.

OK, note to self....................If your not sure if your diff is stuffed, try draining the oil..............this is what came out!



So Ill swap the diff over and hopefully that should fix the problem.

Once again thanks for all you help guys

sticky nicky wrote:OK, note to self....................If your not sure if your diff is stuffed, try draining the oil..............this is what came out!

IMG_2314.JPG

So Ill swap the diff over and hopefully that should fix the problem.

Once again thanks for all you help guys

Check the circlip on the loose axle when you do. That gap means the axle was just bouncing freely there, it wasn't locking into the diff housing. Like others have said, the circlip is probably broken or missing. Maybe the axle bouncing against things, instead of rotating inside them, is the cause of your broken pieces in the diff. Replace diff, check axles, replace clip if necessary. Sorted.