Big time center diff problems

[Tim Sexton]

Thanks for all the replies.  I did some more testing on the car yesterday,
and If I mess with the diff lock rod enough, eventually it will engage.
After that, I can use all 6 gears just like normal, however, it malfunctions
shortly thereafter and I am back to grinding when I let the clutch out in
any gear.  I can actually let the clutch all the way with the transmission
in gear, and the car doesn't move.
    I checked the shift linkage, and it is aligned correctly.  When the diff
is engaged, the car shifts just fine, I just can't make the diff stay that
way for very long.
    Could it be a malfunctioning diff lock actuator?  Does the rod for the
diff lock need to move an exact amount for it to be fully locked or
unlocked?  I can visually see the rod being moved when I lock and unlock the
diff with the switch.
Thanks,
Tim Sexton

Huw Powell wrote:

> >     I just finished replacing the clutch on my 86 4000csq and now the
> > transfer case seems to be stuck in neutral.  The clutch seems to be
> > operating fine, however, when you put the car in gear and let out the
> > clutch the transfer case grinds like crazy and the car doesn't move.
>
> Well, it's not a transfer case, but anyway I'll take a stab it this - it
> doesn't sound like you are actually getting the car into gear.
>
> The center diff. is always "engaged," it is just locked or unlocked when
> you switch it.
>
> The 4kq shift mechanism is a real nightmare of a setup.  You may
> discover that one of the many rods or levers is not properly attached,
> or that it is not properly adjusted.
>
> I like to use reverse when doing a "seat of the pants" adjustment (read:
> no proper tools).  Since 1. you can get confirmation that it is actually
> in the gear you think it is from the backup lights, and 2. reverse
> requires you to push down to avoid the lockout mechanism, it's the most
> "precise" gear to fiddle around with.  Then just make sure the others
> engage as well before washing your hands.
>
> The "proper" way (I think) is to have the tranny in neutral, ie at the
> middle "rest" position, and use a tool to hold the shift lever dead
> center while tightening it up.  But that is tough without the centering
> tool.
>
> --
> Huw Powell
>
> http://www.humanspeakers.com/audi/
>
> http://www.humanthoughts.org/