Date:         Tue, 02 Jan 1996 22:24:08 -0800
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Steve Hoge <steveh@emu.com>
Subject:      Re:89 syncro, binds in tight turning

> My friend has a 89 syncro, just purchased. When turning tight. The
> wheels
> bind and have a lurching sensation. The characteristics seem like the
> rear
> diff is locked. VW machanic say the CV's are fine. He said it is a
> normal
> function of a Syncro. 

It *is* normal for the Syncro to feel a little funny when tight turning,
but I don't get the lurching or binding; at certain speeds I seem to get
"pulled through" the turn, which is actually a positive handling
characteristic.

The different steering sensation occurs since the circles tracked by the
front wheels are appreciably larger than those tracked by the rear, so
there is a front/rear rotation-rate difference which the viscous
coupling "doesn't like". However, this represents a "front slip/rear
traction" situation, the reverse of the normal 4W-engaged scenario, and
I have been curious about whether the viscous coupling would engage in
this case (Syncronauts help me out here.)  This would be somewhat
related to the question: do you get 4WD in reverse? (since the torque on
the viscous coupler from the drive shaft is also in the opposite
direction.)

I have been warned by mechanics *not* to make tight U-turns in a Syncro
(do a 3-pt instead) because of these considerations...is it just an old
wive's tale that this is hard on the front drive?

Of course, the symptoms described also sound alot like a locked
differential - it should be pretty easy to determine whether the rear
diff-lock is on (if you have one - if so, make sure the front display
light, which gives positive feedback, isn't burnt out) - but a *front*
differential which has locked up :-( might give similar symptoms, along
with other steering anomalies.

Steve Hoge
'77 AutoLoaf
'89 Syncro GL