P 
> >
> > Hi Paul,
> >      I have a VW training manual that says "When the difference in
> > speeds between the flange shaft and the pinion shaft is less than 6% the
> > viscosity of the silicon fluid is low. This allows the plates to slip,
> > resulting in no transfer of power between them. However, when the speed
> > difference between the two shafts beccomes greater than 6%, which could
> >  
> > but I was interested in what VW said about the 6% difference in speed. I
> > wonder if the coupling will not lock up with the two shafts spinning at
> > a 6% difference for a long distance?  I wouldn't want to try it. I think
> > you should get the tires matched as closely as possible. The front diff
> > is very expensive.
> >
> > Todd Francis
> > 91 Tristar
> > 86 westy syncro
> 
> How much in tire diameter could 6% represent?
> Peter Larsson
> 1994 EV Crewcab Syncro

 Hi,  Would it be that the tire diameters can't be more than 6%
different in diameter? Or would gear ratios play a part in the equasion?
If it is just Tire diameters you can take the exact diameters of each
tire and mathimatically figure the percentage of the difference in size.
Todd