build a custom width high pinion dana 44 for my XJ and have had quit afew enquiries. So I put this build and tech page together. I hope this helps others that plan on going down this road. I will continue to add on to the post as I have time to type it up. The build is done and works well.
In the late 1960’s Ford directed Dana to design a high pinion, reverse spiral 44. The first 3-4 years of production used a kingpin knuckle design that is obsolete, and difficult to play with. One could use an early housing and press aftermarket inner-knuckles on to fix this limitation. About 1970, Ford began utilizing a ball joint inner knuckle that is very common. The early to mid 70’s F-100 and F-150 Ford axles utilized drum brakes, and either a 5 bolt or 6 bolt spindle pattern.. This should not be confused with wheel bolt pattern. The spindle bolt pattern attaches the spindle to the outer knuckle. All F-100’s and F-150’s were a 5 on 5.5” wheel bolt pattern and they are about 67” wide, WMS to WMS. These early Ford units are desirable because Ford welded the suspension mounts (Radius Arm “C’s” as they are commonly known) to the axle tubes. Beginning in mid-to-late 1976, Ford began casting the suspension mounts as part of the inner knuckle assembly. These mounts take up a considerable amount of tube, and if you want to use any other than Ford’s suspension design, they will vex your efforts. In 77-79, the vaunted an highly prized “Camper Special” F-150 was available. This is basically an F-250 axle with 5 on 5.5” outers which you are going to ditch anyway (more later). Don’t pay a premium for this unit unless you have the odd desire to run leaf springs, as the extra material in the leaf spring perch makes it difficult to mount link mounts. The same applies for the F-250’s of that vintage. In late 1979, Ford revamped there whole front suspension design, and introduced the highly undesirable, Twin Traction design.
With this information in hand I set out to look for a 1970 to early 1976 Ford F-100 or F-150 High Pinion (Reverse Spiral Cut) Dana 44. I came across a early 1976 F-150 axle that I purchase for $175.00.
I decided on those years because Ford welded the suspension mounts onto the axle and I had plans on shortening the axle to a waggy width (more on that later). I also want to run 5 x 5.5" wheel pattern.
I tore the axle down to the bare housing to get a good look at what I was up against.
I soon realized that the highly charished 1976 Ford F-150 axle with disc brake, was not going to be the cost savings I had planned on. The hubs, rotors, and hub lockouts were not salvagable. This is why you can use a 1970 to 1975 F-150 drum brake axle. You will most likely discard everything from the balljoints out.
I then cut the suspension mounts for the radius arms of the axle. This step was fairly easy. Just take cation not to cut to deep as to cut into the axle tubes.
I then took the time to grind the remaining welds off the the axle tubes and took a wire brush to the axle to clean it up. Take your time on this step it will make the build cleaner and nicer to work on.
At this point I contacted Bob and Matt from TNT Customs about making a truss for a High Pinion 44. I have used the skills of Matt and Bob many times in the past. Being one of the first to run their Dana 30 Truss I know there attention to detail and quality was second to none.
After a few long talks with Matt and Bob about narrowing the axle to a Jeep Wagoneer width so I could use Wagoneer axles we came to the conclusion that to get the pinion inline with the front output shaft of the transfercase we would have to narrow the axle equally on both sides. This would cause me to purchase custom length axles instead of using stack axles out of a Wagoneer. Because I was planning on purchasing Chromoly Axle Shafts this was not much of a problem.
I did some research and came up with these measurements comparing the different years of High Pinion Ford Dana 44's and Jeep Wagoneer Axles.
1978-1979 BRONCO (Length 18.91 in.; 30 Spline;Driver Side; ) 39143
1978-1979 BRONCO (Length 33.91 in.; 30 Spline;Passenger Side; ) 39144
1972-1977 BRONCO (Length 18.31 in.; 30 Spline;Driver Side; ) 38809
1972-1977 BRONCO (Length 27.94 in.; 30 Spline;Passenger Side; ) 38810
1968-1979 F-100 PICKUP (Length 18.91 in.; 30 Spline;Driver Side; ) 39143
1968-1979 F-100 PICKUP (Length 33.91 in.; 30 Spline;Passenger Side; ) 39144
1975-1979 F-150 PICKUP (Length 18.91 in.; 30 Spline;Driver Side; ) 39143
1975-1979 F-150 PICKUP (Length 33.91 in.; 30 Spline;Passenger Side; ) 39144
1980-1984 WAGONEER (Length 15.8 in.; 30 Spline;Passenger Side; ) 39459
1980-1984 WAGONEER (Length 32.12 in.; 30 Spline;Driver Side; ) 39461
1974-1979 WAGONEER Disc/Drum;Drum/Drum (Length 33.19 in.; 30 Spline;Driver Side; ) 39339
1974-1979 WAGONEER Disc/Drum;Drum/Drum (Length 14.69 in.; 30 Spline;Passenger Side; ) 38808
Using the measurements for the 1975 to 1979 Ford F-150:
18.91" on the Drivers Side
33.91 on the Passenger Side
And the measurements for the 1980 to 1984 Jeep Wagoneer:
15.8" on the Drivers Side
32.12" on the Passenger Side
I originally was going to shorten the axle to a Wagoneer width which would make you shorten the drivers side 3.11" (18.91"-15.8"=3.11")
and shorten the passenger side 1.79" (33.91"-32.12"=1.79")
But with the decision of shortening the axle equally on both sides to keep the Pinion where it should be it came out that I should shorten the axle on both sides 2.45"
NOTE: If you decided to to narrow the axle to a Wagoneer width you would only be 0.66" off of center. The problem you run into narrowing your axle to a Wagoneer width, and keeping the coils center, is that the drivers side coil bucket will end up into the cast portion of the center section where the drivers side axle tube is installed. I truely believe that you can run 0.66" off center without ill effects.
To mark the correct spot where I was suppose to cut the axle, I took a few measurements. I needed to know how far out the inner knuckles sat out from the end of the tube. With my dial calipers I got a measurement of 0.130". So I added that to the 2.45" and mark the axle tube at 2.58" from the outboard side of the inner knuckle. I then cut the inner knuckles off with a sawsall just inside the welds on the axle tube. This gave me clearance to use a chop saw to cut the axle tubes to the right length. If using this method make sure that you set up the chop saw level and that the axle tube is also level so you achieve a perfect perpendicular cut.
You will have to remove the remaining portion of the axle that is still left in the inner C's. To do this you will need to remove the weld portion on the inboard side of the inner C's. The most efficient way to do this is to clamp the inner C into a vise and grind the weld down till you are flat with back surface of the inner C. At that point you will want to grind in a cone shape removing mainly the portion of the axle that is still in the inner C. You will soon see a circular line appear. This tells you that the axle portion that is still in the inner C is ready to be pressed out or knocked out with the proper size drift and a hammer.
Once you have the inner C's cleaned up, and the axle cut down to the width desired, you are ready to install them back on the axle. First you will need to now what your Pinion angle will need to be. I took the measurement off the Dana 30 that was installed in my Cherokee to get a base line. To get this measurement you will need some type of angle finder. I have two types, a dial type angle finder and a digital angle finder. Both work extremly well.
The best way I have found to get the most accurate pinion axle is to take it from the differential cover mounting surface when the differential cover is off or the flat portion next to the differential cover where you would install a case spreader.
Note: This picture is not of my axle and used for reference only.
I came up with a measurement of 13.5 degrees on my Dana 30 with my Cherokee lifted 9 inches. Due to the added higth of the Dana 44 subtract 0.5 of a degree to come up with a desirable pinion angle.
Here is a rough estimate of what your pinion angle should be with a desired amount of lift:
NOTE: All these estimates are based on using a Jeep Cherokee and should be checked.
6 inch lift = @10 degrees
8 inch lift = @12 degrees
9 inch lift = @13 degrees
With your pinion angle figured out you will need to level the axle. I used jack stands and cardboard to achieve this. Once you are level support the pinion yoke to the desired pinion angle.
It is time to set your caster angle on your inner C's. Ideal handling comes from about 4-7 degrees of castor. I’m very happy with 5 degrees. With the axle on a stand, you can measure the caster by putting an angle finder on the bottom flat of the inner knuckle where the ball joint presses in.
Set the inner C against the end of the tube, rotate it to the desired Castor angle and make a reference mark across the inner C to the axle tube. Set the inner C aside and use a square to mark reference line down the axle tube. This will give you a guide to keep your inner C at the proper Castor Angle will driving on the inner C. Just keep the mark that is on the inner C aligned with the mark down the axle tube. Remember not to drive the inner C to far on. You must stop at the previous measured point at which the inner C stuck out past the end of the axle tube. In this case it was 0.130".
You will need to repeat this process to both sides. Try to be a precise as possible. Your castor can ussually be off from side to side by .5 degrees without any effects to your driving characteristics. If you are off more than .5 degrees you should remove the side that is farthest from your desired castor angle by driving it off and repeat the install process.
Once the inner C's are installed back on the axle tube. Weld them into place.