85 4ksq rear diff

["Cory Meyer" <meyer@netconx.net>]

I have owned my Audi for a whole year now.  It's been pretty good to me.
$600 for Exhaust.
$200 for clutch MC
$100 cap, wires, plugs and rotor
$50   A-arm bushings.  (includes tools)
----------
$950 later and I still enjoy it.

One problem.
My rear diff. doesn't lock.  Living in Iowa I had will have the chance of
needing all the help I can get without using AAA.  I have a feeling it is
probably the vacuum.  I spent my hard earned $15 on a stupid Hayes manual
which doesn't cover anything Quattro wise.   so... is there some easy cheap
(Under $50) way to fix this.  Hopefully it is just a disconnected vacuum
line.

Any suggestions.
Thanks.

Cory Meyer
meyer@netconx.net
85' Mars Red 4ksq w/bright red calipers.