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Hi guys

So I got the car down the garage to diagnose an occasional clonk that seemed to come from the rear of the car when selecting D or R. The garage removed the driveshaft, rotated the diff and the noise is coming from the diff. On the plus side better the diff than gear box.

Has anyone heard of the rear diff being an issue? Are there any modifications to strengthen the diff?

I’m assuming the issue has been caused by my 2/3 gap having the rear drive axels removed when refining this area or perhaps the worn drive shaft support bracket which I’ve now had replaced.

Never heard of another case. You just got lucky.

Yes, just my kind of luck.

I don't think there's anything special about the diff. You should be able to get it rebuilt easily enough, I would have thought. No LSD or anything.

You probably want to make sure that it's not the centre propshaft bearing that is actually clonking. That's a fairly common failure.

Thanks Ben. They said they removed the prop shaft and rotated the diff, this would isolate the prop bearing? Hopefully they’re able to tell from that if it’s a fault within the diff. Sadly I’ve got to put my trust in them as I’ve not got the time, tools or skills to do the work myself.

I would be skeptical of the diff being the issue as well... I'd suspect the rear diff bushing, an axle, or the center support bearing before I would condemn a differential. Althought it would be easy to cut to the chase - They should be able to drain the diff fluid and observe metal shavings if the diff is clunking from high backlash tolerance. I'd have them do that before you rebuild a diff at the very least.

Frustratingly the diff wasn’t the issue. The garage aren’t charging me for the labour changing the diff, as it was their call to change the diff, and have found a prop shaft to change on Monday.
Prop makes more sense to me as there is still this slight vibration plus the occasional clonk.