A4 B6 1.8T FWD 5-speed manual HFD Gearbox / Front differential knock (very bad)

[BarnaBK]

I got a very bad knock when I take off from stationary, as I release the clutch, its really annoying, sounds like an old truck.

I recorded a few videos to show you as accurately as possible:

Clutch release: A4 B6 1.8t knocking rattling on clutch release - YouTube
Differential knock: Audi A4 B6 FWD gearbox / front differential knock - YouTube

Is there a separate front differenctial in our FWD 5-speed manual version or it comes all together with the gearbox?
Does the front diff have a separate oil chamber outside the gearbox, and does it need separate oil change or its the same chamber as the gearbox? Would some nice thicker oil help at all?
I just changed oil in the gearbox, didnt help..

I see whats coming but I just dont want to believe that I have to replace the whole gearbox , just spent a small fortune on timing belt and service, new clutch etc, I am trying to find an excuse or other explanation.

Any ideeas? Cheers

[Crasher]

The diff is integral but when the box was replaced, were all bolts replaced as what you have sounds like something is loose.

[BarnaBK]

The diff is integral but when the box was replaced, were all bolts replaced as what you have sounds like something is loose.

I didn't had the box replaced, just the clutch, and for the clutch new bolts were used, but thats all I know about the bolts... The mechanic swares down that he tightened everything.

[Crasher]

You have to remove the box to do the clutch, he may well have tightened everything but a large number of the bolts/nuts are one time only and this probably was not the first time the bolts have been out so they can stretch or even snap.

[BarnaBK]

You have to remove the box to do the clutch, he may well have tightened everything but a large number of the bolts/nuts are one time only and this probably was not the first time the bolts have been out so they can stretch or even snap.

Well, we will find out soon, I found a gearbox in good condition for a good deal, so will get it replaced this week.

I am thinking to get new set of bolts though, any ideea where to find them?

[Crasher]

Yes, the only source is the main dealer or TPS if your chap has an account.

[BarnaBK]

Thanks mate