A while back I asked about differences between pulleys on syncros and 2wd
vans and about the two part rear main seal on the syncro. The first
question I had was if the 3 groove pulleys on the two types of vans were
the same. From the part numbers, I concludded they were the same pulley and
they are. The second question I had was if one can use a regular main
seal with a pulley off a syncro and again the answer is you can. So I did
this and 500 miles later, my rear seal is leaking like a sieve (again).

What I did not know at that time was what the 2 part seal looked like... The
two part syncro seal is composed a thicker rubber seal and a steel cup. The
steel cup is press fit on to the pulley (or so it appears) so that it appears
that the pulley itself is different between the syncro and 2wd engines. The
steel cup also increases the diameter of the pulley (and thus my guess is
that it tore the 2wd main seal I had installed during my rebuild). So, with
the correct syncro rubber seal in my possession, I hope to finally have a
clean nonleaking engine this coming week. Thanks to Kyle at volks motorsports
for pulling out a couple pulleys and seals for me to examine...

dave