I recently noticed a 'klunk' sound when I put my auto kombi in reverse and also when it dropped back a gear going up a hill etc etc... so it was off to the automatic shop for me (thinking it would all be $$$) and anyway the problem was minor but a major problem to solve. Apparently the front engine mount (towards the front of the van) had undone itself and fallen off- its a metal plate that sits in a rubber mount and then is bolted to the chassis to keep the engine and auto gear box nice and tight.... sounds easy enough doesnt it?? well these things are IMPOSSIBLE to find at short notice.. there were none available anywhere in australia when I spent 5 hours calling just about everyone in this wide brown land and VW stopped making them 15 years ago!!
Well the great guys up here at Action Automatics made up their own and had me back on the road in a couple of days for approx $100...:kiss

Yes, it's a common problem and the do break!
When ever I* get to the wreckers I keep an eye out for good ones, that's about your only hope.
Last time I needed some Hardings still had a few.