Thanks Joachim for your very informative reply to my question. Very
nice to wake up to news direct from the horses mouth so as to speak
(i.e Germany; the home of our much loved syncro's.) I teach at a
college and if half my students had your command and confidence at
English I'd be more than happy. Do permanent 4WD drive shaft syncro's
have front and rear diff locks like the viscous coupling syncro's? Are
their 4WD capabilities as good as a VC syncro with diff locks, or do
they (permanent drive shaft syncro's) manage just as well without diff
Are the permananent drive shaft syncros only good for sand. What about
mud, steep terrain, boulders and river beds,snow and gravel/dirt
tracks and fire trails.Can you drive on any of these in 4WD.
Also is it true that you cannot engage 4WD on the fly in non VC
Syncros; you have to stop before engaging.
Phil are you saying that permanent drive shaft syncro's always engage
in 4WD in the 'G' and reverse gear or did you mean the VC syncro's.
Many thanks everyone.
just to answer you some questions:
If you are installing a "permanent 4WD" (in fact it isn´t, cause you
should never ever use this 4WD-mode on asphalt) you are just
replacing the VC in the front-gearbox with a bush, which also fits to
the gearing of the driveshafts.
To lock or unlock the 4 WD-mode you have to install some additional
parts at the rear gearbox.
But coming back to driving:
You can use this permanent 4 WD (which correctly means, that you do
not have a center-diff; the VC normaly acts as that) on every
slipping underground. There is no difference if you are driving on
mud, sand, slipping gras, rocks, gravels etc. JUst be carefull using
it on slip-proof underground, such as asphalt, cause you dont have a
center-diff which corrects different turning-speeds of the front and
Compared to a working (!!!) VC i realy don´t see an advantage, except
you are playing in deep flowing sand. There the VC has the problem,
that it needs a turning-difference of the axles to transmit torque
from the rear to the front.
If you have some more questions, just feel free to write a mail to