Budd:

Redline is good.  Lots of listees use it.  Some listees use Mobile.  I
don't know about the others.  I spoke with a Redline tech twice recently
about what to use and here's what they reccomend  for the syncro:

Front Differential: Redline 75w90 Gear Oil  (which is an API
GL-5+[exceeds requirements for GL-5 and GL-6] hypoid gear oil designed
for differentials)

Transaxle: Redline MT 90 Manual Transmission-Transaxle Lubricant
(which is a 75W90 API GL-4 gear oil designed for transaxles)

Both of these oils meet all VW syncro specs.  You could drop down a
notch in the weight on the transaxle oil according to Redline...slightly
smoother shifting....but I opted for more high temp protection as
provided by the 75W90.  Shifting improved noticably...a common refrain
from those who switch to redline....but it's expensive.  About $90 if I
recall.  I think you need 7 quarts total.  4 for the transaxle and 3 for
the diff, but it's been a few months.  You better recheck Bentley....I
know it's in there.  I think it's in a different place than the 2wd.

If you can borrow or make (like I did) a pump to pump the oil into the
impossible-to-reach-with-a-funnel filler-holes, you will save yourself a
lot of frustration.  You also need a 17mm allen wrench.  Get the socket
version.  Much easier to use.

steve

Budd Premack wrote:

> It is my intention to change the oil in the transmission and front
> differential of my 86 Syncro.  Would synthetic oil be the preferred
> choice?
>  If so, are there any distinctions between Redline and Castrol?
>
> What weight would be appropriate for ambient temperatures that range
> from
> -20 F in the winter to 95 F in the summer?  Would 75W/90 be best?
>
> What is the capacity for the Syncro 094 transmission and front
> differential?  (I have perused my Bentley without success.)
>
> This oil change is scheduled for Monday, so quick responses would be
> most
> helpful.
>
> Budd Premack
> 86 Syncro, 84 Vanagon (soon to be for sale)
> 73 Super, 64 Bug (soon to be for sale)
> Minneapolis, MN (Land of Sky-Blue Waters)