Newbie's guide to solid axle swaps
The most important thing you need to know before you attempt any kind of modification this grand is that you can never have enough information. Do plenty of research before making even your first parts purchase. You'll be happier in the long run if you know what you are getting yourself into ahead of time. Modifications of this scale have two things in common: they are not cheap, and they are more involved than you think. Do plenty of research so that you know what to expect time-wise, labor-wise, and financial-wise. This is far from an exhaustive source of information. Do yourself a favor and find some more. Realize also, that your swap will likely be very different than mine, due to changes in what you may feel is necessary for your vehicle. This is only a guideline, please treat it as such.
I heard about the benefits of altering my front suspension initially through these forums, where up to now several members have swapped in solid axles beneath their Explorers or Rangers. Much of the information you see here was gathered by myself from these members, which include Tom Davis, Kampy, Riffman, Sandy Balzarini, Dale Tiessen, Knut Orloff, and Rick Horwitz. I may or may not be forgetting someone, my apologies if that is the case. All of these people have in common that they chose Dana 44 solid axles from early model Fords to adapt to their rigs. After hearing much of their positive feedback after performing their swaps, I was convinced that this was the route I needed to take. I have to admit, however, that the deciding factor in my decision was so that I could run an Oxlocker under my rig. I'll talk more about this piece of equipment a little later.
Choosing an Axle: The solid axle that I chose came out of a 1979 Ford Bronco. I am of the opinion that the best axle to look for, in my situation at least, was a solid Dana 44 axle from a 78-79 Ford Bronco or F-150. Both of these vehicles are full sized, which means that the axle would have to be cut down before it could be placed under my vehicle. This is still preferable to taking a Dana 44 from an older Bronco, which was very close in size to the Explorer. This is because the early model Bronco's, known as Early or Classic Bronco's, were equipped with low pinion front axles, whereas the full-size Bronco introduced in 1978 was high pinion, which is also known as 'reverse cut.' What this means is that the point on the differential where the axleshaft connects was below the axle tube in early year Bronco's, and the 78-79 Bronco's axleshaft met the differential above the axle shaft. In practical terms, this means that the driveshaft angle is greatly reduced by installing a high pinion axle in your front end, which is greatly exaggerated by lifted trucks, which further increases this angle. The high pinion differential also provides better ground clearance, for both the differential and the driveshaft. Extreme driveshaft angles can lead to binding and eventual part breakage. This is not as much a problem in the rear of a vehicle as it is in the front, because the increased driveshaft length in the rear serves to reduce the driveshaft angle to manageable levels. It is possible to cut the axle tubes and re-weld a low pinion differential in an upward degree that would place the pinion at the same angle as the incoming driveshaft. This is not desirable, however, as it leaves the ring gear inside the differential inadequately soaked in gear oil, which could lead to premature equipment failure. Also, in 1977 Ford Bronco's began to be equipped with front disc brakes, which of course is more desirable than drums. Companies such as Dynatrac and Currie can make axles to your custom specifications if the task of preparing a used one is not desirable. Be prepared however, as these custom axles are not cheap.
Choosing a running width: Choose a running width that is right for you. In my opinion, it is best to have the front axle width match closely that of the rear axle. If swapping both axles out of a donor vehicle you may decide that the width does not need to be modified for your application. In my case, that would mean running full size axles under a smaller sport utility vehicle. The axle that I acquired from the 1979 Bronco measured a full six inches wider than the axles under my Explorer. By running the axles full width, you will save on the cost of cutting them down, which runs close to $200 per axle housing side, as well as $55 dollars per axle shaft. You would, however, still find expense in that new spring perches would need to be fabricated to match the springs up to your frame, or by finding some way of mounting all of your vehicles spring hangers outboard of the vehicles frame. Mounting the radius arms this way is much weaker than having the brackets mounted under the frame. The advantage in running full-width axles is that your center of gravity is effectively lowered, which helps to offset the effects of lifting . This results in a more stable vehicle that is more difficult to roll, and also allows for larger tires. The disadvantages are an increased turning radius, a loss of mobility, and the inability to fit on some trails.
Cutting down the Axle: For my application, I decided to cut the axle down 5.85 inches on the passenger side. I had thought that cutting by this amount would allow me to install an Early Bronco axle shaft in the event that mine were to break. However, I found that my measurements were off by 0.12 inches. It is much cheaper to use a shaft from a stock vehicle than to have one custom made. A stock Explorer's axle width is 58.3" and the big Bronco axle width is 65.25." Cutting 5.85" out of the passenger side leaves me with a 59.4" axle width, which is 1.1" wider than the Explorer axle. I could cut the axle down to the Explorer dimensions, but the added inch will help with the driveshaft angle, since the differential on the big Bronco's are slightly more toward the passenger side than the differential on the Dana 35 Explorer axle. The passenger side inner axle shaft on a full-size Bronco measures out to be 33.91," and the correct inner shaft from an 71-77 Early Bronco is 27.94." The length of the axle shaft found in 65-71 Bronco's measures 28.06," but this vehicle uses a Dana 30, not a Dana 44. The difference between the 78-79 Bronco and the 71-77 Dana 44 equipped Bronco is 5.97 inches, which is how much you would have to cut from the full-size shaft to accept those from the Early Bronco. I had made the mistake of cutting down my shaft using the early Bronco Dana 30 measurements, which left my axleshaft 0.12 inches short. When cutting the axle shaft, it is better to send the shaft somewhere to get it cut and re-splined. Do not cut the axle shaft in the middle and re-weld it, as this leaves a weak point in your driveline. There are various companies that can do this for you, such as Moser Engineering and Dutchman Axles. I used Dutchman Axles, and the cost was $55 dollars.
Matching up the Rear: Most Dana 44 solid axles come equipped with a 5 lug, 5-1/2 inch lug configuration. The stock bolt pattern on the Explorer is a 5 lug 4-1/2" configuration. Unless I wanted to worry about carrying two spares, the rear axle bolt pattern needs to match up to that of the front. The Dana 44 was only offered briefly with a 4-1/2" lug spacing in Dodge vehicles, but this system is less than desirable as it is a hubless design, and its smaller parts are much weaker than the 5-1/2" axles that could be found on most Fords and Jeeps. This leaves only the option of converting the rear axle to the same bolt pattern as the new front axle. This of course, will require the purchase of new rims with the correct bolt pattern. The stock axle shaft flanges in the Ford 8.8" are just barely to small in diameter to simply be re-drilled to the new pattern. This requires that the axle shafts be replaced in their entirety. Moser Engineering and Dutchman Axles offer 5 lug on 5-1/2" bolt pattern along with new axle shafts. Dutchman Axles will run about $240, Moser $295. The stock 8.8 axle flanges are just barely too short in circumference to be drilled out to the new bolt pattern, so they have to be replaced. There is no way around this in my case.
This swap can be done for far less than I spent on it, and there are others on this board who have done so. I am in the middle of this swap myself, so there may be more parts that I add to this list in the future. Here is my current parts list:
36x1250x15 TSL SX (5) $800
www.4wheelparts.com
15x10 Black Rockcrawlers (5) 5 lug on 5-1/2" $275
www.4wheelparts.com
Gears, install kits, D44, 8.8 $400
www.Drivetraindirect.com
ART Brakes, D44 $400
www.Appliedrotortechnology.com
Mile-Marker Hubs $55
www.autozone.com
C-Bushing set $45
www.broncograveyard.com
Radius arm shock mount $15
www.broncograveyard.com
Bronco Coil Towers $40
www.broncograveyard.com
Oxlocker, D44 $750
www.Drivetraindirect.com
Rockcrawler driveshaft $150
www.highangledriveline.com
Extended shock mounts $32
www.bcbroncos.com
Coil Shims $60
www.sierrabronco.com
SkyJacker extended brakelines $70
www.tyres1.com
Rockcrawler 5.5 Black coils $160
www.wildhorses4x4.com
1979 Bronco $751
www.ebay.com
Old Man Emu 2" lift rear springs $400
www.4wheelparts.com
Dutchman 8.8 Axle Shafts 5.5 lug config. $240
www.dutchmanaxles.com
TA 8.8 Diff cover $150
www.ebay.com
Warrior Shackles $55
www.jcwhitney.com
Mountain Offroad anti-wrap spring perches $45
www.mountainoffroad.com
Mountain offroad shock brackets $20
www.Mountainoffroad.com
Powertrax No-Slip. 8.8 $400
www.Natltire.com
Trail Ready Steering Linkage $350
www.performanceunlimited.com
Trail Ready Trackbar $150
www.performanceunlimited.com
Rebuilt Calipers $60
www.autozone.com
Differential Guard $70
www.4wheelparts.com
Labor
Install gears, lockers $400
Cut Long side D44 Axle shaft $55
www.dutchmanaxles.com
Cut D44 Housing 5.85 inches $150
Cut/Weld trackbar/ steering linkage $50
Fab Trackbar Mount $50
Drill Drums to 5.5 lug config. $35
www.dutchmanaxles.com
Weld rear perches, shock brackets $90
Custom transmission crossmember $150
Total Cost: $7,175
Thanks a ton Randall!!
