Installation
Transfer Case
The first step was to remove the driveshafts, the
crossmember/skidplate and then the 231 transfer case. Next,
I removed the exhaust from the header back. A new exhaust
would have to be installed so I Sawzalled some of it to
speed the removal process (why bother with seized bolts when
you can just cut 'em off?). With the back end of the motor
supported with a floor jack, I temporarily bolted the D300
to the tranny. It fit perfectly although the front output
end of the case hung down quite a bit. Not much I could do
there. Re-indexing the way the case mounted to the tranny
was not an option.
With the case in place, I was able to take measurements
which I needed to fabricate a new crossmember/skidplate out
of square tubing. In retrospect, I think it would be easier
and save space if I just hacked up a stock
crossmember/skidplate. I'll probably do that later this
year. I also marked out which part of the floor pan needed
to be pounded out in order to make room for the transfer
case shifter. An easy way to do this (thanks to Wil for
this tip) was to jack up the entire vehicle and then lower
it onto a tall jackstand which will then push against the
part of the floor which needs to be pounded up. While I had
the skidplate removed, I cut off the exhaust hanger hoop
which is mounted on the passenger's side of the transmission
mount. I then welded it onto the driver's side of the mount
so it could be re-used when the exhaust gets re-routed.
I used a torch to put the necessary bends in the shifter so
that it crossed over the transmission and came up in the
same place that the factory shifter did. An alternative
method I've heard of is to simply turn the transmission
tunnel cover around so that the shifter plate/boot is on the
passenger-side.
The speedometer cable and breather tube hooked up to the
Dana 300 without problems. Well, that's not quite accurate.
I did manage to break the nut which holds the speedo gear
assembly in the transfer case. It's a cheap, cast metal
part so be very careful when tightening it. Fortunately, I
was able to obtain a replacement the very next day from
Gary's Autowrecking.
Front Axle
With the help of a pitman arm puller (thanks, Gord!), it
wasy very easy to completely remove the steering linkages
and the front axle. The D44 bolted in easily but things
became difficult when I saw how little clearance there was
between the drag link and the leafs when the axle was at
full droop. Basically, the angle was so steep that the drag
link would hit against the passenger-side leaf spring. I
solved this by welding 1/2" tall pads on top of each perch.
This gave me the clearance I needed and I suspect this is
one of the reasons why I didn't have this clearance problem
when I did the Rubicon Express SOA with my stock axles: the
"anti-wrap" perch plates they used provided that 1/2" of
clearance.
With the new tie rod holes I had drilled into the steering
arms, I was able to use my stock YJ tie rod but I had to get
it shortened by 3 inches. I could've had a thicker one
built but that would've reduced my turning radius because
there is very little clearance between the tie rod and the
front of the diff cover. I was able to re-use the stock
drag link after I screwed the tie rod ends further into the
link, there by reducing its overall length.
I was hoping to use a front CV shaft but there wasn't enough
room for the CV. It would've hit the auto tranny's pan
under easy axle movement. I had to use a regular
two-u-joint driveshaft in the front.
The stock brake lines bolted up to the F150 calipers
perfectly.
Rear Axle
The rear axle installed even more easily than the front. I
used an early Ford Bronco front CV shaft for the rear. It
was short by 1 or 2 inches but would suffice for temporary
street use. With the Jeep sitting on all fours, I used a
scissor jack to adjust the pinion so that it was just a few
degrees shy of pointing directly at the rear xfer case
output shaft.
With both the front and rear axles, I used a "fresh" set of
used YJ springs. To these spring packs I added a main leaf
(with the eyes cut off) from my old packs.
The parking brake cable worked with the Scout brakes but it
was a bit short when the axle was at full droop. The brake
line junction block for the YJ is on the driver's side,
opposite to the Scout layout. This moving the YJ's hard
brake lines onto the D44 housing. As I expected, one of the
lines was seized on so I had to make a new hard line for the
passenger-side. To mount the YJ's junction block (T-block)
onto the D44 axle housing, I welded a bolt onto the top of
the driver's side tube. I slipped the block over the bolt
and secured it in place with a nut.
By the way, if you haven't already guessed, the Scout axles
use the 5 on 5.5" bolt pattern. This meant that I had to
buy a new set of wheels and swap my tires onto them while I
had the Jeep supported on its frame.
Exhaust & Driveshafts
I took the back roads to get to the local muffler shop where
they re-routed the exhaust so that it stayed on the driver's
side until it got close to the gas tank where it then bent
up and over the driveshaft and exited in the standard
location.
The drive to the driveshaft shop was much quieter. There
they lengthened, re-furbished & balanced the Bronco CV shaft I had in
the back and re-tubed a skinny '88 YJ front shaft. Because
of its small diameter (but 1/8" wall) and low mass, I didn't
have it balanced and even so, there is absolutely no
vibration when I drive with the hubs locked in.
Brakes
I was planning on using a CJ master cylinder which I heard
works well with this swap but it wouldn't bolt up to my YJ
booster. I decided to forego this modification and keep my
stock mc/booster. The result was the same old soft pedal
but much better braking performance. Rob Bryce gave me a
list of vehicle brake specs and the late CJ mcs seem to have
the same mc piston size as the YJ mcs. I think the reason
the CJ stuff might have worked better is because it's
possible to adjust the pedal/push rod leverage. I might try
that on my YJ by buying one of those adjustable rods.
