DEREK, DO NOT DO THIS, as I have admonished numerous times
The GL rating is wear additive formulation, you need a GL4 cause
VW says you do.  My local parts place stock 80W90 GL4 only for about
$2 the quart.  My best rec is as usual Redline MTL, perfect for this
app, correct weight, GL4 formulated, synthetic (which is fine, too
slippery?, what BS) about $7.50 the quart, call (510)228-7576 for a
local dealer.  Indeed the front diff does take GL5 rated as it has no
synchro hubs, the VW synchro hubs are designed for metal compatibility
with and only with a GL4 oil.  Indeed I used a GL5-6 in my Quantum
4wd and it started howling about a year later (though likely from
terrible under oil condition, not the GL5 but who knows),  if I
owned a 4wd van, I would spring for the $32/qt VW (my price here),
lets see $120 in oil, $1200 in transmission, you make the call.  The MTL
should be an excellent choice though, call them any verify it for this
app,
then buy it GPR 800-321-5432 a good source if a local one is not
available.
Get some Redline Water Wetter for the cooling system while you are at it
someone recently conjectured that agitation of micrbubbles in the
coolant from not "wetting" the head a common problem in big truck
diesels unless they use a wetting agent like this, wasserboxer is same
configuration, wasserboxer has problems, an ounce of prevention and all.

John

==================================
Alistair Bell
==================================

	its not a case of "slipperiness" but one of syncro eating 
additives in GL-5. Well atleast according to Redline. D. Haynes claims that 
that is an old idea and that the sulfer compunds responsable for the 
corrosion are not present in modern GL-5 oils. I don't know about that, 
up here i have "smelt" trans oil that is disctinctly sulphurous.

i put Redline MTL (GL-4) in my trans this winter, I think it was an 
improvement (replaced the non-synthetic)

alistair

___________________________________
Derek Drew                           New York, NY
drew@interport.net (main address for e-mail)
derekdrew@aol.com (alternate/backup, checked infrequently)