2-Big Broncos 4x4 Technical White Papers

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Automatic Hubs/Transfercase Conversion

Well the T-case itself cost me $400 with exchange of the old one.  Thee
shifter was about $30, and the Warn hubs were $80.
The installation was pretty easy, though I must admit I was sorta
nervous about it before hand.
1.  Drain the fluid from the electronic case and disconnect the wiring
harness at the shift motor.  Then disconnect both drive shafts from the
2.  Put a jack underneath the t-case to support it and begin to unbolt the
case.  I believe they are either 1/2" or 13mm bolts, you will need a
flex-joint socket to get the upper bolts off as the is not enough clearance
between the body and the t-case housing.
3.  Once the case is unbolted you can go ahead and slide it off the output
shaft of the tranny.  The case is not very heavy (I'd say about 70lbs.) so
one person and a jack or two people can lower it quite easily.
4.  There is a gasket that sits between the tranny and the t-case so you're
probably going to want to replace it at this time.  Once the old case is out
you are ready to put the manual shift one in.  On the end of the tranny there
is a locating pin which corresponds to a hole in the t-case, line these up
and bolt in the t-case.  Make sure both the t-case and the tranny are in
neutral is it will make lining up the splined shafts much easier.
5.  Once the t-case is in place it is time to install the shifter.  Get
inside the truck and peel back the carpet over the tranny hump.   You will
need to remove the kick panel next to the e-brake as well as the entry guard
on the drivers side.  I also removed the front seats and the center console
to have more room.  Once the carpet is up take a hammer and chisel (or
screwdriver) and begin peeling away the plate covering the shifter hole. It
is held in with some type of silicon sealant and is sort of a pain in the
butt to remove.  Once the plate is out you can go ahead and install the
shifter and screw it to the floor, I believe the screw holes were already
6.  Once the shifter is in you need to connect it to the t-case.  A word of
caution here, there are several different lengths of linkages.  The linkage
I got with the shifter was marked C-6 and ZF, and it was too long for my
AOD.  I went back to the wrecking yard and they gave me one marked T-18
(they could not find any marked AOD).  The T-18 linkage was a bit short but
I actually prefer that becuase now the shifter handle sits further forward,
out of th way, when it is in 2WD.  The linkage is connected to the t-case
by polyurethane grommets which can be had a the dealership parts counter.
they are sort of hard to get in, I ended up using two pairs of pliers on either
side of the linkage to pop them on.
7.  Once everything is in the only thing left is to reconect the drivelines.
If you want you can remove the wiring harness through the hole in the floor
while the seats are out, it comes through the floor about six inches behind
the drivers seat.  The shift control module is located behind the passenger
side kick panel and is held in by a couple of screws.  The last thing I did
was to remove the trim panel housing the shift switches and the switches
them selves and replace it with a blank trim panel.
Hope this helps, if you have any questions let me know.
Rade Spasojevic - 1990 XLT Bronco

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