4K Diff Lock Servos

[eletourneau at verizon.net]

Hello,

I have a 1988 VW Quantum Syncro; same drivetrain as the Audi Quattro 4K,
and I have a question on the differential lock servos.  

After looking over some failed servos, I have the idea that if the rubber
boot covering the output shaft rots away and leaks, that one side of a
valve will fail.  -- Can anyone confirm this, and suggest a source for
replacement rubber boots?

Ed

And Merry Christmas to all.