Narrowing a HP Dana 44 for a Jeep TJ Wrangler
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DANA 44 FRONT AXLE TECH
The goal of this project is to build a mostly bolt in, mostly stock width front high pinion Dana 44 for a Jeep TJ.
Desired final specs:
60.5” wide wms-wms
5x5.5” wheel bolt pattern
Strong enough to handle 37” tires with a stock motor.
Factory style and spacing link and coil mounts.
Factory location trac-bar mount
Factory location sway bar mounts
Factory location shock mounts
Complete beefy steering with near factory geometry
After researching and reviewing a ton of other HP 44 swaps and searching high and low for an axle - the decision was made to start with a leaf spring Ford 1978 F250 HP Dana 44. After measuring and measuring I decided to narrow the axle to use factory 1980’s Jeep Wagoneer axle shafts, which can be found on the shelf at most 4x4 places or only 2 days wait via the internet/mail order.
Using wagoneer axle shafts give you an almost equal length cut on both sides which allows you to keep the pinion location virtually the same as the axle came with from the factory.
Long side: 34.75-32.12=CUT 2.63”
Short side: 18.60-15.80=CUT 2.80”
Difference = 0.17” divide by 2 to balance the axle side to side = 0.085” pinion location change. I think you would be hard pressed to measure 0.085” of pinion offset once the axle is installed. (If you use the 1976-1977 radius arm mount style Ford axles this almost equal number is not the case, another popular build came to this conclusion and used custom axle shafts to keep things centered).
The next task was creating factory style links/mounts, in a effort to save a ton of time and engineering a T&T Customs axle truss with all the factory style mounts pre-installed was ordered. I ordered one for the leaf spring style Ford HP Dana 44 with the full understanding that I would need to modify it to fit our narrowed housing. When the truss arrived I made a bunch of measurements and decided to cut 2.75” off each side and grind a little on the axle housing and a little on the truss to re-center it on the narrowed axle housing. All went very smooth and the truss fits like a glove!
1978 Ford High Pinion F250 axle with all the factory brackets removed
Once the calculations and decision making was done - the hard work began of narrowing the housing and prepping it for the truss. The end yokes are ground and hammered off. The tubes are cut down to size.
The pinion angle was set to 5 degrees and the caster was set to 7 degrees - that should allow plenty of adjustment once the axle is installed. With everything checked 10x, everything was welded back together.
Axle narrowed and test fitting the waggy shafts before final welding
One thing that was new to me in all of my previous narrowing project was removing the leaf spring perch for the truss. Per the T&T instructions the drivers side leaf spring mount is trimmed by 2.375” to allow clearance for the truss and the lower control arm mounts. In retrospect this is a terrible idea!!! If you remove that portion of the perch you also remove the factory alignment hole for a case spreader - which is 100% necessary for installing an ARB. We well deal with that blunder later... In a moment of not thinking I hacked off the perch. It went very easy. I cut it into 3 pieces and popped it right off. I used a bandsaw and cut off wheel to make the cut.
With the truss narrowed and massaged it was set in place and leveled while holding the pinion angle. Again after 10 measurement checks the truss was welded on in short stitch welds.
Cast spring perch removed
Truss centered and aligned. The truss is set to 0 degrees with 5 degrees
of pinion angle.
ARB installed and axle painted.
After the truss was welded on and the lower control arm mounts were welded in place, the axle was primed and hauled off to have the ARB installed. That was when I realized that cutting the spring off was a bad idea. The carrier spreader works by fitting into the holes on the edge of the housing and pressing out. The drivers side hole was cut in half by following the truss install directions. To make the case spreader work a few pieces of metal were welded back onto to the axle the recreate the hole for the spreader. It worked OK - but it would have been a lot easier if I had not cut that much off the spring perch and instead cut the truss and made it fit the axle.
To finish out the build Synergy ball joints were installed in standard F150 knuckles. I reused the brake caliper brackets and spindles but used all new hubs, rotors, bearings and Warn Premium locking hubs. 4340 Chromoly inner axle shafts, Spicer ujoints and factory outer axle shafts should provide plenty of strength for modest wheeling and 37" tires.
The truss kit comes with all new bushings and hardware the upper control arms and the shock mounts.
Steering was built with all 1.5"x0.25" DOM tube and 7/8"x18tpi weld in bungs. Standard 3/4 ton tie rod ends were used with left and right hand threads for easy adjustment. The tie rod was placed under the knuckles to clear the factory style track bar mount. I tried it flipped to the top using tappered inserts in the knuckles but the tie rod hit the track bar mount when turning. The sway bar mounts were welded on after the steering was resolved to insure no clearance issues.
Here is a picture of the tie rod and track bar mount interference. Raising the track bar mount would have solved it - but the TJ this is going in only runs 4" of lift and still uses the stock location for the track bar.
Close-up of the track bar mount location on the truss.
All in all the project went very smoothly and the axle should last a long time and outshine any Dana 30. The T&T Truss was very nice and made things go very quickly - I just would cut the spring perch differently to allow a case spreader to work. I might also order the truss with an aftermarket style raised track bar mount.