Date:         Tue, 19 Sep 1995 18:47:29 -0400
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         SyncroHead@aol.com
Subject:      Re: Diff Locking Questions and Trip Report

In a message dated 95-09-18 17:16:49 EDT, TFORHAN@hr.house.gov (Tom Forhan)
writes:

> In both the owners manual for my Syncro Westie and the Bentley,
>     pictures of the diff lock controls show a single push-pull switch
>     mounted below a diagram of the chassis/powertrain, front wheels to the
>     left, with a single green indicator light between the two rear wheels.
>
>     Pull the switch out, the rear diff locks and the light goes on, natch.
>     Indeed, this actually happens on my van, like it is supposed to!
>
>     However, on my van, there are also two more little lights (or places
>     for lights, in my van they don't light up) indicating the center and
>     front differentials. I can't find these lights in the Bentley wiring
>     diagram, nor pictured anywhere else.
>
>     I deduce three possible explanations: (1) front and center diff
>     locking were an option, undocumented in the manuals, that I don't
>     have, and if I did there should be three seperate push-pull switches?
>     (there are places for two more to the left of the first).

Tom,
I think that your option #1 is closest to being accurate.  While the rear
locking differential was an option in the USA bound Vanagon Syncros, I have
seen pictures from other countries (Australia and S. Africa I think) that
also have a front locking differential. Indeed, the front differential on
your Syncro will have a mounting pad for the locking servo actuator, but no
actual penetration into the differential and (I assume) no internal parts
needed for locking.  From this, I assume that the central position on the
dash assembly is for a center differential lock, although I've never even
seen pictures of this.  One Syncroite on the list (Derek Drew) bought a
locking front differential from Germany and was planning on installing it.
(Derek, have you done this yet? I'd love to hear how it went).  BTW, although
the manual says to drive straight ahead to make the locker engage after
pulling the knob, I've found that a slight curve seems to engage it much more
quickly.  I think that by driving exactly straight, the locking mechanism
doesn't work it's way around to the locking point.  Derek, Tim Smith, What's
your experience on this point?


>     Saturday I took the Syncro Westie to the Range Rover Test Area, on an
>     abandoned farm located in the DC area (The importers US headquarters
>     are located nearby). This is not a publicized area, but there are no
>     gates, though they have used bulldozers to build some small berms
>     across the entrance road which filters out Toyota Camrys and the like.
>
>     We let the Goodrich AT tires down to 20PSI (I use 40 on the hi-way),

It's been my experience that airing down to 20PSI won't gain you much.  I've
found that 12-14 PSI seems to help alot.  One rule-of-thumb I've heard is to
air down until the sidewall height is 1/2 of it's normal height.  This was
around 12 PSI for my old Bridgestone All-Terrains.  I haven't measured it yet
on my Goodrich ATs.

>     got green-to-go on the diff lock, slipped it into the granny gear, and
>     lumbered over the berm. The whole area is about 100 rolling acres,
>     criss-crossed with trails that climb up and down through open, scrubby
>     areas and some woods. Many of the trails were heavily rutted, with
>     high centers that could easily catch the bus. It was very dry -drought
>     back here lately- the soil is clay, and I could imagine that after a
>     heavy rain, this place would be a total mess. We bounded (well, twice
>     we got into second gear) over hill and dale, dodging ruts, tree limbs,
>     and dirt bikes. I am certain that this is a good place to learn
>     the limits of vehicles and drivers.

O.K. enough! enough!  I can't stand to hear any more about all this off-road
fun while my Syncro is broke!  :-(

Jim Davis
87 Syncro
88 Wolfsburg