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Preparation
Front End
I started by completely disassembling the front end. The
diff fluid was very muddy and contained water. I decided to
have all new bearings and seals installed. But before I did
that, I first had to address the issue of converting the
housing into a spring-over axle configuration. Because the
diff housing is so far to the side, the only
reasonable way to do this was to grind a spring perch into
the side of the housing. While I was at it, Rob convinced
me to angle this new perch so that the pinion pointed
towards the xfer case output. This provided extra ground
clearance under the pinion yoke and allowed me to use a CV
shaft. Grinding this perch into the housing was
surprisingly easy.
When Rob & I dis-assembled
the front end, it was obvious
that I would have to replace
all the bearings, seals, etc.
This axle was heavily abused...
but for $65, I wasn't disappointed
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This is the start of
the perch mounting pad
I ground into the top
side of the front D44
(circled in red)
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Once the mounting space
was completed, I tack welded
a half-inch thick plate to
serve as the spring perch.
I added four small gussets
and then got John Edgar to
weld it up for me at the
same time he welded my yokes
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The Scout axle has zero degrees of caster. Tilting the
pinion upwards will result in negative caster. SOA
conversions generally require five degrees or more of
caster. It is for that reason that I had to adjust the axle
yokes' caster. This was an excrutiatingly difficult
process. I had to carefully grind away the welds which
secured the yokes to the axle tubes and then pound on the
yokes with a heavy hammer. After a lot of grinding and
pounding, I finally got them moved to a decent angle. One
thing to be aware of is that if you set them for too much
caster, the steering arms may be tilted up so much that the
drag link & tie rod will collide with the spring packs
(applies only to SOA setups).
When adjusting the yoke
caster angles, I used an
angle grinder with a thin
wheel to grind away the
weld securing the yoke to
the axle tube. Here you
can see the rust-coloured
line which is the seam between
the tube & yoke (indicated by
a red arrow). If this line
goes right around the tube,
you can begin hammering the
yoke to adjust its caster
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In the foreground is the
yoke which has been set to
the new caster angle. In
the background is the original
caster. Big difference, eh?
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Once the yokes were positioned just right, I had a
professional welder weld the yokes in place using special
rod which would work with the cast metal in the yokes. He
also welded a spring perch plate onto the flat spot I ground
into the housing. For the driver's side perch, I made one
from square tubing and welded it on myself.
For shock mounts, I welded some simple studs onto the back
of the housing so that they were perpendicular to the tube.
I welded them directly to the tube because I wanted to
eliminate all the annoying hardware that hung below the
axles. I was planning on raising the upper shock mounts
once I got my Jeep back on the road.
The housing was pretty filthy so I had it steam cleaned and
re-painted. With that done, I handed all the pieces plus
new bearings, seals, etc to Grant Klavatalks who
re-assembled the front end and ensured that the ring &
pinion gears were correctly setup. While he was doing that,
I also had Grant drill & ream new holes in the steering arms
so that I could mount my YJ tie rod six inches from the
center of the ball joints. This would allow me to use the
existing pitman arm without reducing my turning radius by
very much. I also bought some 1976 Ford F150 4x4 front
calipers rather than rebuilding the ones which were on the
axle. I used Ford parts because they fit in the axles but
used a smaller brake line fitting which was identical to the
size already used on my YJ. I swapped the stock diff cover
for one from a Ford reverse rotation D44. These covers are
designed to be used on the front diffs so they are flattened
in front for added tie rod clearance, they're approx 1/8"
thick for rock protection, and the fill hole is higher up
which is useful if your pinion is tilted high.
With the front perch and
yokes tacked in place, I
hauled the front housing
over to John Edgar's place
where he welded everything up
using rod which was amendable
to joining cast & mild steel
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The new hole I had
drilled for the YJ tie
rod is circled in red.
Turning radius is almost
as good as before.
You can also see the
shock mount which I welded
to the axle tube, raising
it 3-4 inches higher than
the factory YJ location
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Rear End
In comparison, it was much easier to prepare the rear axle
housing than the front. As with the front, I completely
disassembled it and steam cleaned it. New bearings & seals
were purchased, as were new brakes and drums.
The spring perches for the rear were purchased from Lou
Feger's Racing (http://www.loufegersracing.com/). They were a
clamp-on design which allowed me to mount the axle to my Jeep
without welding the perches in place. This allowed me to adjust the
pinion angle once the Jeep was resting on the wheels rather than trying
to calculate/guesstimate what the pinion angle should be. I also had
the option of adjusting the pinion angle after taking it for a few test
drives. Then, once I found the perfect angle, I could weld the perches
in place. The only fly in the ointment, so to speak, was that the adjustable
perches were designed for Ford 9" axle tubes which are 3" OD, where as the
Dana 44 tubes are 2.75" OD. To rectify this, I bought two short lengths of
pipe with an OD of 3" and 1/8" wall thickness. Then I cut them in half
lengthwise to fit them around the axle tubes where the perches were going to
be mounted, and welded them in place. This brought the effective axle tube
OD to 3". Lower shock mounts were similar to the front except that the
studs ran parallel to the tube. They were mounted in line with the tube
to maximize ground clearance.
Transfer Case
I purchased a yoke which would work with a CV shaft using
1310 u-joints. I also changed a couple of seals.
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