There was nothing wrong with the KYB shocks from Bus Depot that went
onto my '90 Westy last week.  Problem is more likely on the van and/or
with previous install....
BTW, if you are in the Pacific NW area, the KYB shocks that came off of
my '90 were in very good shape (I was being paranoid and trying to solve
a minor handling problem) and I kept them.  If someone needs a set of
used but good shocks, get in touch, yours cheap.