Re: quattro center diff lock actuator ...

[Dave Lawson <dlawson@digitalglobe.com>]

Steve writes...
>
I did look at the newer 5k quattro tranny with the center diff lock 
actuator mounted on it and compared it to the older 4k quattro tranny
I have that had the center lock connected via cable.  It turns out that
the new actuator bracket mounts to the bolt that holds the shift linkage 
cover, so it should be possible to retrofit on the old tranny, and there 
is a guide for the linkage that also mounts to existing bolts.  The thing
that could cause a problem is the connection to the actuating rod coming 
out of the back of the center diff ... the older diff has a different 
connecting mechanism and it appeared that this mechanism was attached 
with a rivet rather than a bolt.  There was a boot over the rest of the 
mechanism so when I get a chance I'll check it out ... but this one de-
tail might make it very difficult to convert an urq with the lock actuator
in the back to the front.  

Perhaps there's someone out there that has actually done the mod ...
<

I've BTDT, (been there drivin' that). Did this mod to my urq transmission.
As steve says, it's a bolt on for the servos and rod. Took a bit of thought
on how to attach the actuating end of the rod.

For the original implementation on the urq tranny, a cable is used to 
actuate the center diff. The servo is mounted on the rear diff. It's the 
cable case which moves(towards the front of the car) and pushes in the
engagement mechanism. The inner cable mounts to the outside of the
center diff and doesn't move. The casing mounts to the engagement
mech by attaching to a small plate with a hole in it. Let me describe this
again...

To engage the center diff a metal rod slides into the center diff housing. The
difference between the early and later cars is what is attached to the
end of this rod. The urq has a small plate with a notch and hole in it,
that the diff lock cable attaches to. The later cars have a hole drilled 
through the rod and no plate. The servo mounted to the tranny uses
an actuating rod(different than the rod which penetrates the center diff
housing). The end of the servo acutating rod bends 90 degrees and is
inserted into the hole drilled into the other rod.

The problem lies in the fact that the urq tranny doesn't have the engagement rod
with a hole drilled in it. My solution was to get a short/fat bolt whose diameter
matched the whole in the small plate. I then drilled a hole through the bolt. I
installed the bolt through the hole in the plate and then put the actuating rod 
into the hole in the bolt. Put some loctite on the bolt threads, installed a lock 
washer and nut and tighted it up. So far so good.

I had it real easy doing this mod, my tranny was sitting on my rolling
surfboard on the garage floor. Not sure how difficult it will be with the
tranny installed in the car. 

Next up will be electric push-bu.... (shshshsh not yet)
-
Dave Lawson