The front diff. can also cause this vibration problems. What happens is
the seals blow, and the 2 different fluids get mixed. Once stopped
for any length of time they seperate. On start up the different
weights of the fluids cause a vibration until the fluids mix again.
This also means your diff. is dead.

            Eric                   86-VW4x4
            vw4x4@fyi.net          72-240z
            Pittsburgh, PA USA     1936-Chrysler

On Fri, 4 Jun 1999, Gary E Thaxter wrote:

> >2) I've read about the mixed results people have had with rebuilt
> >driveshafts - it seems like only Mark >Drillock has had a positive
> >experience (Oceanside Driveline, (760)439-9718). I'm wondering if he's the
> >only >one, of if his has gone bad as well. And if I put a rebuilt on the
> >van and the vibrations come back, how >could I be sure that the driveshaft
> >is to blame and not some other front drivetrain component?
>
> I tried the local rebuilder with no luck.  The vibrations were still there.
> I thought that maybe there was something else wrong (front diff or wheel
> bearings or driveaxles)  I later found out that the driveshaft place I went
> too was not the best.
>
> I sent the shaft out to another place, but have not reinstalled it yet.  I
> had to change one front wheel bearing, so I got my axle rebuilt while I had
> it out.  I am going to do the other axle and bearing soon. Also, when I
> loosened the diff mounts, one of the bolts broke and my mount was pretty
> rotten.  I ordered new mounts, so while I have the diff out, I am going to
> get someone to open it and check bearings etc, and it needs a seal.
>
> I will have the whole front end redone (wheel bearings, driveaxles, diff
> mounts, diff bearings checked, and driveshaft balanced with new universals)
> before I put my driveshaft back on.  If it still vibrates, I will have a
> 1986 syncro GL for sale (with new front end).
>
> I'll let you know what happens and if it really is worth it to get the
> driveshaft redone, or if you should maybe try genuine VW gold plated
> spanking new, or maybe check other front end stuff.  I'll have everything
> done by month's end, I'll get back to you then.
>
> >My van does drive very nicely w/o the driveshaft, but I bought a syncro
> >because I wanted the 4WD, so I'd really like to get it fixed at some
> >point.
>
> I know what you mean.  Last weekend we took the syncro camping and I found
> some new trails.  I missed a chance to do a river crossing and would have
> had some really good picture opportunities.  Good pictures on the bikes,
> but a van in the river pic would be nice to add to the scrapbook.  Too, I
> missed the mud drag-race last year because of driveshaft/vibration probs.
> Not again this year!  I'm sure I can take the 4/6 cyl. class. . .
>
> Gary Thaxter
>