Waggy D44 Front axle:
It is very smart to keep a stock axle in your rig IF it makes sense to do so. On the positive side: It’s already in there, you already own it, and all the mods for it should not require too much custom work to get it to all work together.
The high pinion Dana 30 front axle that is in the YJ is a pretty good unit. The high pinion design is quite strong as it runs on the drive side of the ring gear. Upgraded to TJ one piece axle shafts and decent u-joints, it is very good to a 33” tire and even a 35” tire if you are very careful. Very careful.
But breakage is not the only limiting factor to consider when deciding to keep or swap out the D30 for a stronger axle such as a D44.
The brakes on a D30 are smallish, the wheel bearings are a non-serviceable unit bearing design and the knuckles do not accept a high steer arm. There is a way to add lock-out hubs to the axle, but it uses a weaker hub than the normal D44. Also, the axle tubes are not as beefy as the D44.
So, even though you may be able to get it to stop breaking on ya’, getting it to stop and steer may cost so much that you could have been into a 44 for the same cost. In my case, running a 37” tire put me at the very precipice of disaster, so although many would suggest a Dana 60 front end, a Dana 44 can be built to survive 37s if you don’t drive like a teenager. The ball joints, wheel bearings, brakes, axle tubes, etc of an old D44 were built to run under ‘trucks’, not mini SUVs. That beef pays off when you hit the trails.
I wanted to use a Ford High Pinion D44 out of a ½ ton truck or Bronco. They are a bit wider at 65” than the Jeep D30 (61”) but that is not so bad. The H/P design is strong and they have a 5 on 5.5 bolt circle pattern which just happened to match the wheels I already owned. However, I could not find one anywhere, junkyards, classifieds, etc. Here is a great link to all the info you could imagine on the H/P Ford axles. Read-up before you buy as not all of the Ford axles are desireable.
http://77cj.littlekeylime.com/Links/Links.htm An amazing source of info on D44s in general
My second choice was a Wagoneer axle out of an 80’s full size Jeep. They were only offered in a low pinion design and the lug pattern is wrong (6 on 5.5” bolt circle) but the width is good (around 62”) and they come in both drivers and passenger side pumpkin locations. That makes the choice of transfer cases a bit more open. They are very easy to find in junkyards, etc. I paid $250.00 for one I yanked by myself out of the local Pick-A-Part complete disc to disc. It came out of a 1987 Waggy, drivers drop (diff on drivers side to match the Ford NP205 doubler setup I have in waiting), and was in good condition.
Follow along as we adapt this old soldier of an axle to our YJ by narrowing the spring perch locations, changing the lug pattern by adapting a mix of Chevy and Ford parts, and getting it to steer where I want it to go. We will also get the brake lines moved to better fit the Waggy axle and add 4.56 gears and an OX locker. I will not get into the gear or OX installation per se as that was done by a local fab shop, JC Fab and Design. Most folks pay to have gears done, but I will get into the actual set-up, adjustment and operation of the OX locker as we go along in the build-up process.
Step 1: Making It Fit
The Waggy axle is darn near a bolt in to the YJ. It came from the factory with the springs under the axle like the YJ, so if you are staying SUA (I am), you are ahead of the game. Unfortunately, the spring perches are 1” too wide to get the center pins of the springs to sit correctly. The YJ is 31” center to center, the Waggy is 32”. To get there from here, you need to re-drill the hole in the cast section of the spring perch at the diff housing ½” in towards the middle of the housing. The welded-on spring perch on the other side needs to be removed from the tube and moved in ½” as well. If you are careful, you can re-use the old perch and re-weld it on. On the diff side, in order to keep enough meat in the new hole I was drilling next to the old one, I measured very carefully ½” over from center, marked it with a punch, and then, before drilling, cut the head off a bolt and dropped the shank into the old hole and welded it across the top of the opening. Then I drilled the new hole in a size that accepted the center pin of the springs. Measure very carefully both sides in from the knuckles or some really good point of reference before you drill so the axle will sit squarely in the Jeep. You will likely need to grind/cut some of the housing away to allow the springs to not interfere with the cast housing. This allows for the springs sitting closer to the diff housing. I used a thin cut wheel on an angle grinder and a flap wheel to clean it up. Don’t cut any more than necessary. NOTE: The perch you see hanging out underneath the cast in perch was to be the new SOA perch before I changed my mind and stayed SUA. I removed it later.
That process leaves you with a spring perch that is not entirely there….that is to say it is not a complete square pad since you moved the spring over more than the factory intended. I wanted to make up for that, so I made a small bridge section and then added a ¼” plate on top of that. JC Fab welded it up for me using a special welding rod that will stitch the cast iron to the steel reinforcement I made. Welding cast iron to steel is an iffy process so it is best to see a pro or at least get good advice before proceeding.
As far as u-bolts go, it is a matter of grinding until they fit. I have seen some examples on the net where folks have taken a LOT of the webbing off the diff housing. That is a bad idea in my opinion. If you are going SOA, it all changes a bit and you just need to make a new perch that fits on top of the housing/tube in the right location. Remember to keep it the same height as the other side perch, either by adding to or taking way from one or the other sides until they are even.
Attaching the springs: Home made u-bolt flip.
Staying SUA, I wanted to keep the hangy-down parts as slim as possible. There are some typical set-ups like the Con Fer u-bolt plates, but they hang down pretty far. I decided to do a u-bolt flip and make the spring plate fit on top of the axle tube/housing. This really keeps things below the spring pack to a minimum, but it does require a bit of fabbing. Check Dynatrac for a ready to buy version of what I did at home.
http://www.dynatrac.com/products_ubolt.html
I had some 9/16” x 8” x 2.5” wide square-bent u-bolts made up locally for $9.00 each. I took some heavy wall tubing that the u-bolts fit into (with a bit of slop for good measure) and cut them into short sections as shown. A few tries in frustration trying to keep them true and straight as I fitted them with a 3/8” plate led me to make a jig of sorts to keep it all good. I placed the u-bolts under the springs and made sure the axle was sitting on the axle perch correctly. Holding the u-bolts in place up against the axle tube with a wrap of tape, I was able to measure across all four u-bolt ends until I had a measurement to set the jig to. Then I took 4 bolts that fit very snug into the heavy wall tube and tack-welded them down to my welding table duplicating the measurements off the u-bolts. I slid the sections of heavy wall tube onto the bolts and from here I could cut the 3/8”thick center plate to fit all four sections of tube without them moving around. I also made some arch shaped bridges out of ¼” plate to fit the diameter of the tube and housings perpendicular to the axle. This will keep any bending forces from trying to distort the plate.
To keep the u-bolts from resting directly on the axles, I first cut some blocks out of ½” thick steel about 5 to 6” long a drilled them for the center pin. This would sit between the u-bolts and the springs and I would grind/cut/mill/or whatever a notch that would allow the u-bolts to be recessed into keeping them out of harms way of rocks and preventing them from moving around and bending. I had two concerns with this design. The ½” thick block did not conform to the spring curve and kinda hung out there in the breeze a bit. Besides that, it was possibly not thick enough to resist distortion under stress and perhaps it would allow the u-bolts to de-tension. The final killer was when I tested one block for the u-bolt groove. Sheese…that was a lot of grinding and I was not sure I could cut them any better with any other tool at my disposal. Hmmm. I went back to the drawing board and came up with this. I used the same measurements but in ¼” thick plate, drilled them for the center pin, and grooved the sides a bit where the u-bolts sat to allow for the bend in the u-bolts to sit flush. I cut some sections of re-bar fit them on the front edge of each plate to serve as both protection and security for the u-bolt. The center of the plate needed to be thicker to keep the center pin from being damaged as it hung down past the ¼” plate. I took two very large washers that when combined gave me a ½” thick section that protected the center pin and filled in the section between the u-bolts. They were welded on.
When fit to the axle and springs and tightened down, the thinner wall steel allowed them to be sucked up tight against the springs like I wanted and they do not hang down any further than the 9/16” diameter of the u-bolts. They are not as slick as the Dynatrac ones, but they should do. Remember, when you are SUA, you do not want long spring perches. This works against the curve of the spring as opposed to SOA springs where a long perch helps with spring wrap.
I have one too many studs here: Getting from 6 on 5.5 to 5 on 5.5 bolt circle pattern.
The Waggys were 6 lug axles in keeping with the heavier duty use they saw as a family hauler/exploration/tow rig. If you use the rear D44 or the AMC 20 out of the Waggy to go along with the front axle, you are good to go. However, I was really complicating things by running a Ford 8.8 rear axle out of a ’97 Explorer. That is 5 on 4.5 like the stock Jeep YJ which explains why it is popular for a Jeep swap. So, not only do I have to get the front to match the 5 on 5.5 wheels I had, I also had to get the rear axle to the same pattern. I considered keeping the 6 lug Waggy set-up but there are not too many choices in 6 lug rear axles that fit my needs. I was just over the top of the strength rating of a Toyota Tacoma axle, I did not want the Waggy D44 rear for the same reasons, so I could have had a D60 or Ford 9” built to my needs and kept the custom axles 6 lug. However, then I would have needed to buy new wheels on top of the cost of the axle build. So either I use the free wheels I had and spend money to make them fit…OR…spend more money on new wheels and build a bigger axle than I want to fit them to.
I ended up following the path of changing over the Waggy to a 5 on 5.5 pattern using a combination of Chevy spindles and Ford hubs/rotors and bearings/seals. One good thing about D44s is the commonality or parts. Although there are differences in spindle length and the number for spindle studs, outer knuckles, etc, usually you can mix and match parts like I did between Dodge, Chevy and Jeep if you know what you are doing. Thanks to the all knowing oracle of info, the internet, I was able to get a list of parts to make the change to Ford outer parts and get the 5 on 5.5 lug pattern I needed. See the info below for part numbers, sources and links. I used Parts Mike as the source for all the spindles, bearings and seals.
http://www.partsmikeparts.com/
Hub/rotor assembly (2) from a 1979 F-150 Ford 4WD – Napa Auto # 86297
Chevy small bearing spindle w/1.625” and 1.785” bearing journals (2) – DAN706528X
Wheel seal for rear of hub (2) – Federal-Mogul #4250 and SP Seal kit (2) - 706527X
Inner wheel bearing (2) – Timken #LM603049
Outer wheel bearing (2) – Timken #LM501349
New brake pads for Waggy calipers – NAPA #AE-728A-M (note: there seems to be a difference in Wagoneer VS. Grand Wagoneer pads, so ask for Grand Waggy stuff)
Lock out hubs of your choice for a Ford F150 application.
It all bolted up fine. I installed the new bearings and seals as I went along and the finished look was factory. The good thing here is all this stuff is over the counter and you can use the stock Waggy brake calipers and axle shafts. The Chevy spindle (shown on the left in the pic above) bolts up to the Waggy knuckle and the typical assembly of the hub/rotors is standard D44 stuff. Oh, for the rear axle I will use 1” wheel spacers to go from 5 on 4.5 to 5 on 5.5 and gain some width. See here for another article on converting from 6 to 5 lug.
I decided to upgrade to alloy axle shafts out of respect for my 37" tires and front OX locker. I called Alloy USA and ordered some of their fine high strength shafts and new X-Joints. See article here.
For brakes, I reused the stock Waggy calipers (cleaned up and painted Ford Blue) and fit them with new brake pads. I ordered the excellent Skyjacker braided lines for a 4” lifted Wagoneer. I found the factory hard lines to be out of place for my needs, so on the driver’s side I cut the hard line short behind the shock tower and bent it so it ended up to the rear of the tower, re-flared it and made a tab to hold the hard to soft line connection. This was welded to the frame. I left plenty of slack to make up for wheel travel and I will probably keep the brake lines out of the way with small bungie cords.
On the passenger side I bent the brake line up and continued it past the backside of the shock tower. I extended it with a short section of 3/16” hard line and made a tab like the driver’s side.
Steering: Attaching reigns to my little pony
I had originally purchased a high steer passenger side knuckle from Parts Mike along with a high steer arm and all the hardware. This was to work with the SOA I had originally planned on. When I went to SUA, this was not needed anymore as I could use the stock Waggy tie rod location if I wanted and retain the OE Jeep design where the draglink attaches to the tie rod.
I still need to measure for the draglink, but here are the part numbers of the beefy TREs that Parts Mike supplied.
TRE at the pitman arm - #ES2027L
TRE at the Tie Rod using the Waggy OE set-up - #ES2234R
I also picked up a dropped pitman arm for a Waggy from Skyjacker which Parts Mike re-tapered to accept the one ton TREs that the draglink will use. Although the tie rod is still lower than most rockcrawlers would like, the Waggy axle came from the factory with the tie rod on top of the knuckle instead of underneath and that helps some. Also, the SUA location of the springs will help fend some obstacles away from the tie rod. Besides that, this was much cheaper than going to cross over or high steering. I understand that the stock Waggy draglink can be used, but I had to destroy the one on the donor Jeep to get it out of the truck. I will update the steering and add pics as I get the draglink installed.
I still need to add some lock-out hubs from a Ford application so for now that is it. See how easy that was? Sure!
In retrospect, I wish I had looked harder for a Ford front axle. The extra width would have helped keep the tires out of the leaf springs at full lock and I had underestimated the cost of the swap from 6 lug to 5 lug. One caveat is in some cases the H/P design can interfere with the oil pan or tranny pan. Still, it would be my preference if I could do it over again.
Remember what I said in the first paragraph of the D44 front axle section about keeping the stock axle if possible? Well, with the D35 being the stock rear axle on the YJ, forget I ever said that. It really is a poor choice for anything over 31" tires and even then it is kinda wimpy.
But what axle should I replace it with?
Wow, was this a quandary. Lot’s of sleepless nights, I tell ya. Well, maybe not that bad, but it did consume more hours spent researching and thinking about the options than any other part of the build-up.
The rear axle is subject to more stress than the front since weight shifts under climbing, etc, make what bolts to the rear wheels an important part of the mix in any 4x4 set up. It is easy to go big and strong. 60s, 14 bolts, etc are pretty cheap and easy to find. It is harder to go strong, but not too big, not too expensive and not too wide. There is a fine line in any build-up where you do not want to spend more than you need or end up so overbuilt that you get a vehicle that is beyond the intended use of the rig. Sure Rockwell 2.5 ton axles are dandy and I would never break them but can you just see me driving the Jeep down the highway with those things hanging out into the breeze? Together they weigh more than most of the rest of the Jeep!
So it came down to this:
I even looked at Toyota Tacoma axles and Izusu Trooper axles.
One little warrior that was being discussed more frequently on the boards was the Ford 8.8 out of an Explorer. This is not the full width drum braked version that can be found in F150s, Broncos, etc, but is a disc braked axle that is nearly a bolt in as far as width and lug pattern on a newer Jeep. It has its drawbacks. It is slightly narrower than a stock Jeep YJ D35 by an inch or so. It is a C-clip axle so if an axle shaft breaks there is very little to keep the axle shaft from exiting the axle housing other than the disc brake caliper bolts. It also has a tendency to spin the axle tubes in the housing due to the plugs that Ford used from the factory. Also, the stock carrier is weak.
Does not sound too good, does it? But consider this. The axle tubes make a D35 look like a toy and the R/P is very thick, even when compared to a D44. The factory 31 spline axle shafts are very strong. Jeepers seldom break these, but they do bend them at the flanges every so often. The disc brakes have a nifty factory e-brake built in with an internal drum brake inside the rotor hat. Also, they are easy to find in salvage yards, etc.
They are generally considered plenty strong for 35s out of the box and some guys are beating on them with 37s and 38s and not having many issues. Upgraded with alloy shafts, a full locker (Detroit, ARB or OX) and welded axle tubes, it is a real trooper. Here are some links to other threads and discussions about the 8.8. Read up before you go looking for one as there are some differences betweens years and applications.
- One at Jeeps Unlimited comparing Toyota axles to 8.8s
Caution: We cannot be responsible for other 'mature' content, language, etc on these outside links so click accordingly.
So that is what I did. I paid $500.00 for a very clean 8.8 out of a 1997 Explorer. Not a screaming deal, but about right for So Cal market value.
I had JC Fab and Design in Sylmar, CA, install a Detroit locker and 4.56 gears. While it was there, I had them weld the axle tubes to the housing with a special welding rod to account for the cast housing.
When I got it home, I replaced the brake pads, painted the housing and the calipers (Ford Blue for the calipers) and added some one inch spacers from M.O.R.E. to get from 5 on 4.5 to 5 on 5.5 lug pattern and to gain some width overall. I had to trim the Ford studs about to the 2nd thread on the stud to keep it from protruding past the spacer.
For brakelines I used the soft line on the passenger side as it came from the factory. For the driver's side I bought a passenger brake hose (NAPA part #380528) and used it flipped around on the perch mounting holes. I made this work by reaching inside the spring perch and slipping a bolt through the non-threaded hole in the perch from the inside out and fastening it in place with a nut. Then I took another 2 nuts and a washer to space the bracket out from the u-bolt a bit and added one more nut to fasten it all down. It sounds flimsy, but it worked slick. I used a Skyjacker brake hose and T for the soft line off the center diff and ran new axle tube hardline to fit. I cut into the factory hardline where the pic shows and extended it to meet the Skyjacker braided line. I made a bracket to hold the two where they meet and bolted it to the factory crossmember.
I will go into detail on what I did with the e-brake cables in another update and I still need to weld the spring perches (I was able to remove the factory ones with a grinder and a hammer and re-use them) once I get the pinion angle set. Obviously the factory location of the perches needs to be changed.
I am waiting for some through hardened alloy axles to become available (soon, I hope) and I will replace the stockers at that time.
So, in the end, was it worth it $ wise? You have to figure that the cost of lockers, R/P and any custom axle shafts would be duplicated in any axle I was considering so that is a wash. I did not need to narrow the housing or buy a custom housing (like a Currie 9”) but I did have to buy wheel spacers. I did not have to buy any kind of disc brake conversion kit OR use any custom drilled rotor or brake part. I have more clearance than a 60, more strength than a 44 and a better pinion angle than a 9”. It was still not cheap and if it breaks I will be bummed (and surprised), but it is what I have and it will stay there until it proves itself to be a bad decision.
It does meet my goal of keeping as little full custom parts as possible and walking the fine line of not too big and not to expensive. If I was to replace it I would save and save until I could get a high pinion rear axle of some sort. Those Pro Rock 60s look sooo cool, don’t they? And the Hi-9 is pretty awesome.
Sigh! If only I was rich and not just good looking and talented!
Project Blue Oval YJ gets some axles - A Wagoneer D44 front and a Ford Explorer 8.8 rear (go to rear axle section).
By Michael Troy
