Andy Erskine writes:

>There is a low frequency shake from the transmission. It's intermittent,
>sometimes really bad other times hardly noticable but dissappearing on
>the over-run or when not in gear. It feels like the engine and gearbox
>are wobbling back and forth on their mounts but these look in good
>condition. A parts shop suggested it was a seized c.v. joint. 

Andy, it's possible your CV's are worn, but it's usually accompanied by
noise. I recently had my rear torsion bars adjusted on my '77 van. The
guy over-adjusted them so the rear end was slightly "jacked-up". Of
course I just wanted a level adjustment.

Anyway, I experienced a very noticeable vibration while the rear end was
not level. It was really bad at high speeds. I never knew how bad it was
until I had the torsion bars readjusted. Since then the vibration has
gone. I'm positive that when the rear suspension is not level, that the
CV joints are stressed beyond their normal range of motion. Hence you
get strange vibrations. 

Is your rear end level? sagging? jacked-up?
I'd suggest looking into this before you go out and spend $100+ to
replace each CV joint. I would also proceed with caution if you need to
have your torsion bars readjusted--they can be tricky to adjust. Not
many VW shops will make the adjustment because it requires a special
gauge.

Hope this helps.

Mark Ingles
mingles@iastate.edu