Hello Bill et al;  I had that problem when I first got my latest Vanagon.
I fixed it by removing the instrument covet, removing the speedo dash light
and squirting WD40 directly on the end of the speedo needle shaft.  You
have to use the little hose that they stick to the side of the WD40 can to
direct it accurately.

I had the speedo out to replace (or fix) the digital clock, later and could
find nothing wrong with the speedo at all.  So it seems that the bushing
closest to the needle just dries out over the years, and needs the
occasional squirt.