Early urq diff lock switch?

[ANDREW FINNEY <afinney@bigplanet.com>]

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My urq has the single-pull switch that locks both the center and rear
differential in one shot.  I seem to recall that later models (or
perhaps '84 4000 quattros) had a double-detent switch that would
allow the driver to lock the center differential first, followed
by the rear diff.

Does this alternate switch exist, and is it a direct swap in for
my single-pull switch?  What car can I pull the double-detent
switch from (assuming it does exist)?

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Eric, I am planning this upgrade in the near future. It really isn't all
that bad. All you need to do is run another set of vacuum lines to the
rear of the car under the carpet and rear seat. You use the same vacuum
servo thingies, just connected in parallel, as oposed to the current
series connection. The bentley has an excellent diagram showing the
differences between the old and new systems. Of course you need the two
position switch. This switch comes off a 1984 4000Q. The real upgrade is
to the later style locks with the separate center diff actuator mounted
to the tranny. A number of people have done this, but it requires custom
mods to connect the actuator arm, I think. Good luck. HTH.

Andrew Finney
1983 UrQ