Solid Axle Swap in a 1995 Isuzu Rodeo
The following is a documentation of a solid axle swap that was done on my 1995.5 Isuzu Rodeo. At the time I began the swap, I had already installed a Calmini 3” lift kit, complete with control arms, poly bushings, etc. I ran this set up for just over a year before realizing it’s shortcomings. In attempt to resolve some of these inherent problems, I decided to re-do the front end of my IFS one more time. This time focusing more on strengthening the existing parts and replacing anything that may have been worn. After speaking with Joe Darlington of Darlington Off Road, I was convinced to order a differential drop kit, which would lower the front differential by about 1.5 inches. This would effectively reduce the angle of the cv joints allowing for larger tires to be run and reducing the risk of broken cv joints. To compliment the diff drop, I also got a new set of upper and lower ball joints, and rebuilt cv’s, which I was going to have Travis Rankin heat treat. If finances allowed, I was also going to pick up a set of Stinky Fab heavy duty tie rod ends, when they became available. This, in combination with flipping my upper ball joints, would have given me just about the strongest Isuzu IFS out there, with a descent amount of flex.
Well, winter came and my new diff drop, cv’s and ball joints had to sit in the garage waiting for spring to come around. During that brief period of front end inactivity, I made a purchase that would forever change my perspective on automotive modifications. I bought an arc welder. I had finally freed myself from the chains that bound me to “bolt on” modifications. Now I could even make my own parts. And I did. I fixed myself up a rear bumper, shackles and all, then a front winch bumper, which turned out pretty descent -- for a beginner at least. This new found mechanical ability got me to rethink the plans I had set for my front end modifications. I thought, ‘hell, if I can weld a bumper, and install a lift kit, then why can’t I put a solid axle down there?’ After about three months of trying to talk myself out of another major car project (which was offset by doing some lengthy SAS research), I found myself calling around town for an axle. Here’s the reason: I’ve already got all the parts I need to make my IFS as close to bulletproof as possible for an IFS, however, I’ll be missing one key element in the equation – flex and articulation. Sure, I can dump as much money into my IFS as I want, but I knew that I would still be wishing for a solid axle. Plus, with all the money that I spent on my front end I could have done the SAS swap for probably just a few hundred bucks more. The Calmini lift did serve it’s purpose, however, as being a platform for wanting more out of my ride and allowing me to become more familiar with the mechanics of my front end. Matt Brown, owner of Independent 4x, agreed with me completely. Big surprise.
So I decided to go for it. But I wanted to take it slow, research everything to death, and get it done right the first time. Since the Rodeo was to be my daily driver and my wife may have to drive the car, I didn’t want a monster lift. I figured that running 33’s with a 4.88 gear ratio would be a safe bet. I also wanted to keep the swap as easy as possible – I was already pushing the limits of my mechanical abilities. This meant no coils and no Chevy axles. The swap was narrowed down to either a Toyota axle, or the ever popular Dana 44 from a late 70’s Jeep Wagoneer. After not much consideration, I decided on the Waggy front end for a couple reasons. First off, it’s by far the most popular axle swap seen on Isuzus. This means that most of the mistakes have already been made for me by those who have pioneered Isuzu axle swaps. There is also a basic install kit offered by Independent 4x that contains much of the necessary items for the swap, including spring hangers, leaf springs, steering linkage, etc. Couldn’t be much easier. So the D44 had all this going for it, and the Toyota had Birfields. The decision was a no brainer – Waggy it is. With the 2” Rancho leafs included in the Indy 4x kit, I would be able to keep the lift to a reasonable amount by going spring under in the front and spring over in the rear to balance things out. This would keep me pretty low and still allow me to safely run 33’s and maybe 35’s, if I wanted. Mike Bantz and Casey ??? had similar set ups which I planned on copying and tayloring to my specs.
I found myself a Dana 44 from a 1978 Jeep Cherokee Chief. The axle was locally owned and in good clean west coast condition. This was a perfect year for what I wanted to do. The axles from the ’78 and ’79 Wagoneers had the beefier bearings. Although they didn’t have flat top knuckles in those years (which are needed for running Hi-Steer arms), this was not a concern at the time, as I was going spring under and all the steering was supposed to bolt on without a hitch. Or so I though…
So, that’s how I started the project and the direction that I was taking it. Here’s a brief write up of what I did once I got that 300+ pounds of axle off the back of my truck and into my driveway. What follows are the steps I took to get from point A to point B. I’ve organized this paper into sections to make it as easy to follow as possible.
Even though I had selected what type of axle I would use, I still had a few more decisions to make about how it would sit under the truck:
1. Axle Placement – The further forward you mount the axle, the better your driveshaft angle will be, and you lessen the chance of the pumpkin hitting the oil pan. You’ll also run into less issues with the steering, as the drag link and tie rod won’t cross. However, be ready to do some fender trimming in the front (which is better than trimming down the firewall if the axle is too far back). I originally wanted my axle to be mounted about 2” to 3” forward from the original position, however, it ended up being about 4” to 5” forward. This turned out to be for the better.
For those who are running a narrow axle, you may have issues with the tires rubbing against the front body mount brackets, especially while turning with the wheels during spring compression. This is not an issue if running a wide axle. Mine axle is 65” WMS to WMS, and I did not have this problem.
2. Shackles Forward or Reversed – Shackle reversal is supposed to be better off road, as the axle moves back instead of forward during compression and while rolling over obstacles. The down side to this set up, however, is that when the springs compress, the axle can move back into the oil pan, and the tires can hit the firewall. Although I’ve never done a shackle reversal, there seems to be less room for error when mounting the spring hangers.
I chose to mount my shackles in the front simply because it seemed to be the easier way to get things done. The downside is that I’ll get slightly less approach angle with the shackles out front. In theory, this set up is better for on road use, but worse off road.
3. Spring Under or Over – If you want a lot of lift, spring over is the way to go. This, however, leads to steering complications which I won’t go into since I have no experience with this set up. The obvious side effect to having a lot of lift is that your rig will be tipsy. I didn’t want a lot of lift, and was already intimidated by the steering linkage, so I chose to go spring under. I still ended up with about 6” to 8” of lift.
I’ll admit, I did everything the easy way: Axle forward, shackles forward, and spring under, but what the hell, I’ve never done an axle swap before and didn’t need the added complications. I figured that I could always change things later if needed.
Although most of the axle was in relatively good condition, it was apparent that all the original bushings and seals were still in place. I decided that anything that came into contact with moving parts, short of the axles themselves, would get replaced. This included all the inner and outer bearings, races, seals, and u-joints. I’ve never built a solid front axle, but upon reading the advice of another 4x4wire member, I just started removing nuts and bolts. How complicated could it really be? It’s a 1978 American car part, right? Well, he was right, pretty basic stuff. I used a Haynes manual to help me out with a few things, but nothing was too overwhelming. The calipers were pretty worn, so I picked up some “loaded” calipers from Napa for $35 a side. Although the rotors were in decent shape, I had them resurfaced, to make sure they were flat. I bought all the other necessary rebuild stuff, including the new ring and pinion, from Independent4x. I also needed a new carrier for the pumpkin as the original would only accommodate a ratio of 3.92 and down. My ratio was 3.52, which is probably the same as it’s been for the last 25 years (gear ratio is calculated by dividing the number of teeth on the ring by the number of teeth in the pinion). As much as I wanted to throw an ARB in the front end, the checkbook wouldn’t allow for it. Sure I could have gotten a Detroit locker for about $500, or a Power Trac for even less, but due to the large amount of snow we receive in our neck of the woods, I wanted the option of running an open differential. So I decided to hold out for an ARB. Another thing that helped me out was to tear down only one side at a time so that I had a reference in case things went south. I won’t go into detail on the tear down of the axle, as it is literally only removing nuts and bolts, along with a few cir-clips. The process has also been documented in detail elsewhere on the web and in the Haynes manual.
1. Cleaning - First priority was to clean as much crud off the outside of the axle as possible. I soaked the whole thing in Castrol degreaser and scrubbed everything with a wire brush. After hosing the whole assembly down with water, I was happy to discover that much of the original paint was still intact, with minimal surface rust.
2. Brake Calipers - Brake calipers were removed by unscrewing the two large allen head bolts and prying it off with a screwdriver. Both caliper assemblies were taken to Napa and exchanged for a rebuild.
3. Hubs and hub assembly - After removing the “Explorer” hubs, I decided to get a new pair of Warn Premiums and not have to worry about it again. The hub assembly came apart relatively easily with the exception of the inner snap ring, which had to be sweet talked out with a couple jeweler’s screwdrivers. To get any further in the process, a hub nut socket is necessary. I used a Lisle part number xxxxx to get the job done. It says it’s for a Ford, but worked just fine for my application. The outer hub nuts were on pretty tight and I had to use a good size breaker bar to get them unstuck. After removing the lock washer, the second (inner) hub nuts should be pretty loose and can easily be unscrewed. After both hub nuts and the retaining washer are removed, the entire rotor and hub assembly should slide right off. If you’ll be replacing the bearings as I did, you’ll have to pry off the inner seal to get at the inner bearing and race. The inner bearing should slide right out after removing the seal. The outer bearing should slide out on its own. When replacing the bearings, it is also necessary to replace the races. To remove the races it may be necessary to tap them out with a brass punch. After the bearings and races have been removed, clean all the built up grease from the inner hub assembly as best as you can. Also inspect the rotors for any unusual signs of wear. The inner side of one of my rotors was so badly pitted, it was unable to be turned. Since I had to replace one rotor, I figured that I might as well replace both. The rotors will have to be pressed on and off by a machine shop, or anyone with a press. From here, unscrew the bolts for the brake backing plate, and use a screwdriver to pry the spindle from the knuckle. I removed all the grease from the spindles and attempted to remove the bearings, but was unable. I had the machine shop press out the old bearings for me.
4. Axle Shafts – With everything except the knuckles removed, the axles should slide right out. I had to change the u-joints in both axles following the directions in this how to: xxxxx. Upon inspecting the axles, I couldn’t help but notice that my inner side long shaft was ever so slightly bent. No way to fix that. I decided to go with another Dana/Spicer, as opposed to a Warn chromo -- I’d already spent more than I bargained.
5. Knuckles – The knuckles only need to be removed if replacing the ball joints, as I did. To separate the knuckle from the axle housing, it’s necessary to unseat the ball joints. I used tie rod splitters and pitman arm pullers to no avail. What finally did the trick was smacking the top of the ball joint with a big hammer. I took the knuckles to 4x Doctors in Burbank, CA to have the old ball joints removed, and the new ones pressed in.
6. Re-gearing – After draining the differential, I took the bare housing to 4x Doctors where they installed my 4.88 gears. I didn’t feel like tackling this one myself, as it’s a bit too involved. After all, some guys make a career just out of installing gears.
7. Reassemble – With all the old grease, dirt and grime removed from all parts, everything was wire brushed, re-greased, and the bearing were re-packed. A trick I learned that helped me get the races seated was to let the hub assemblies sit out in the sun, while putting the greased races in the freezer for about an hour or so. After taking the races out of the freezer, immediately place them in the hub assembly. They should slide right in with minimal hassle. When reinstalling the steering knuckles, unscrew the upper ball joint sleeve so that it’s flush with the top of the steering knuckle (you can purchase a special socket for this, but I just modified a 19mm deep socket), then tighten the lower ball joint to the correct torque setting of 75lbs. Next tighten the sleeve to 50lbs, and the castle nut to 100lbs. Everything else just goes on the opposite of how it came off.
8. Painting –I prepared the parts with xxxxx to help the primer stick to any areas where I was unable to remove the rust. This worked well on the rust spots, but became really blotchy on bare metal. After applying a couple coats of primer, the entire re-assembled axle was painted with Rust-o-Leum heavy duty black gloss.
And that’s it for the axle. In my original budget, I didn’t factor in all the parts that would be necessary for a complete overhaul. If you’re flip flopping over whether or not to run an SAS, maybe the following photos will help you with your decision. It goes without saying that the smaller parts are from the Isuzu and the beef is Dana 44.
Nuking the IFS:
If you have a torch, and don’t care about saving old car parts, this step will be very easy. I didn’t have a torch, and I did care about salvaging the parts that I thought may be worth a few bucks. Most of the old stuff came off without a hitch. The stuff that wanted to put up a fight was dealt with by using a breaker bar, followed by the angle grinder if necessary. When all was said and done, I removed every trace of suspension, followed by the steering. After breaking my 1 1/16” Snap On socket (the only Snap On tool I’ve ever owned) trying to remove the pitman arm nut, I decided that the pitman arm would stay on for now. I also left the cast lower control arm bracket which was welded to the frame. This piece also serves as a steering bump stop and makes a perfect brace if I did need to get that pitman arm off, later on down the line.
After removing all the steering parts and the bulk of the suspension, all you have left to do is grind off the pieces that are welded to the frame. What couldn’t be dealt with using my angle grinder was taken care of using the Sawzall. Not the most efficient way to do things, but that was my only option. In addition to going through about twenty 4 ½” cut off disks, this step actually took a lot more time and persistence than I expected. In the end, you can see by the photo that everything came out looking pretty smooth.
Just a quick word of caution if you remove parts using the angle grinder method: The only way to get the angle grinder into many of the tight spaces under the car is by removing the safety guard. A negative to doing this is that you’ll have sparks going everyplace. Combine this with working at odd angles, and grinding parts from on your back, the potential for injury dramatically increases. While grinding the suspension parts off my ride, I always, I mean always, wore a face shield in addition to safety glasses, thick leather gloves, a welders cap, and a thick long sleeve cotton shirt. Despite all this, I still had a good share of sparks running down the back of my shirt and up my sleeves. I never received any eye or hand injuries. I probably should have also worn a face mask, but live and learn. After a couple hours of grinding metal, I started to spit black stuff.
In order to accommodate the added length of the leaf springs, it’s necessary to extend the front of the frame a few inches. If not, your axle will be so far back that you’ll run into all kinds of clearance issues with the steering, driveshaft, and firewall.
Originally, I though I would fabricate and install my frame extension with the IFS still in place to give the Isuzu a bit less down time. Fortunately, prior to starting any of the major work, I found a second daily driver, and down time was no longer a concern. In the end I decided that it would be a lot less hassle to remove everything and “start from a clean slate” anyway.
My frame extension followed suite of what many other folks have done when running shackles up front and springs under. Basically this involves cutting off the two protrusions that stick out from the front of the frame and welding a piece of 2” x 6” rectangle tube in it’s place. The way that this is done most commonly, is to cut the rectangular tube so that it follows the contour of the frame. I did mine a bit different in that I cut the front of the frame flat and welded up a piece of 3” wide plate steel on the face of the newly reshaped frame. I then cut 1 ½” off the side of the rectangle tube, turning it into a piece of 2” x 4 ½” channel steel. From here, I slid a 1 ½” square tube inside the channel steel, spanning the length of the extension, for extra rigidity. I welded the three pieces of frame extension together and did a test fit. After making some minor adjustments to ensure a proper fit against the flat stock plates, I tacked the piece in place. Again, I made sure that everything was level and square, then made the piece a permanent part of the car. To make extra sure that the extension wasn’t going anywhere, I welded a piece of 3” x .250 flat stock along both sides of the extension, and along the edge of the original piece of frame that supports the front most body pucks.
Finally, for even more support, which was probably unnecessary at this point, I welded a couple pieces of 1 ½” tube, which ran across the extension and about eight inches down the sides of the frame. The purpose of this was actually threefold. First, it added strength. Second, they provided the perfect bumper mounts. It was purely by coincidence that the original mounts on my winch bumper were the same width apart as the sides of the frame. Lucky me. Third it also provided a good place to ad a couple of D ring shackles. I also added a couple extra supports which ran under the extension and into the original front of the frame. Again, a little extra support never hurts.
After I got everything welded up, I still didn’t have my leaf springs or spring hangers, so I primed all the exposed metal and waited for the UPS man…
Mounting the Axle:
Getting rid of the IFS was time consuming and messy – not a fun job. Making the frame extension really made the project come to life, but was very tedious. Now this is the part that makes it all worthwhile. Getting the axle placement just right was tricky. I probably spent more time thinking about how to mount the axle than I did actually getting it done. Even after all the thinking and planning, I still didn’t get it exactly where I anticipated.
After I got my 44044 Rancho leaf springs, I mounted them onto the axle with my u-bolt reversal kit (the u-bolts wrap around the springs, instead of the axle tube to maximize ground clearance), I then slid the whole assembly under the truck just to see how everything looked. I was told that with the Rancho leaf springs, I would need to space out my front and rear spring hangers a little less than 46”, on center.
My biggest concern with doing an SAS had to do with certain issues in the steering linkage. Matt Brown sells an SAS steering kit that connects directly to the Isuzu pitman arm. However, I’ve heard numerous reports that the stock pitman arm was not long enough to allow for full lockout of the steering. My other concern was with the drag link hitting the front differential.
After I got my axle hung, I mocked up my steering linkage using the new tie rod ends and some scrap pieces of Douglas fir to serve as the tie rod and drag link tubing. It was immediately apparent that I had clearance issues. The drag link rubbed against the differential cover when the wheels were cranked to the right. To solve this problem, I could do one of two thing: bend the drag link, or put a high steer arm on the right knuckle. I decided to take the expensive route and go with the high steer set up. I felt that since I’ve come this far, I may as well do things the correct way. While I probably wouldn’t have any issues with a bent drag link, the high steer would completely get rid of all possibility of the drag link rubbing against the tie rod and diff cover, and also flatten out the steering linkage, which would eliminate the possibility of bump steer. In the end, it just seemed like the better choice.
Of course, fixing one problem often leads to another. Such was the case with my passenger side hi-steer set up. Although the hi-steer fixed the above mentioned clearance issues, my drag link was now about ¼” away from hitting the passenger side frame rail. To band-aid this issue, I simply lengthened the front shackles. This gave me about an inch of space between the drag link and frame – a reasonable amount provided I install bump stops. For handling purposes, I really didn’t want to make the front shackles longer than necessary, so in the future, I may ream out the pitman arm and attach the drag link from the bottom.
In the end, I’m pretty happy with the way things turned out. On the road, the steering is a little slow and unresponsive, but nothing that I wasn’t able to get used to. The only real issue that I now have is that my ride tends to wander. By adding more caster (installing a four degree shim between the axle and springs) I was able to somewhat fix the problem. Although the wandering feeling is less noticeable, I haven’t been able to eliminate it completely.
Rear Spring Under and Re-gear:
Here again, I turned to Matt at Indy 4x when I picked up my spring-over kit, which consisted of spring plates and spring perches. I also took the opportunity to upgrade to beefier 9/16” u bolts.
Removing the axle from under the truck was a no-brainer. I took as much of the axle apart as I could while the axle was still hung. It took a long breaker bar to get the brake calipers off, and a big rubber mallet to pop off the rotors. After the rotors came off, it was necessary to take the parking brake drum assembly apart in order to remove the parking brake cable. The ABS sensor and differential vent tube also had to be disconnected prior to removing the axle.
When trying to remove the axle shafts, there are four bolts that attach to a backing plate on the inside of the axle housing. After removing these bolts, I figured that the shafts would slide right out. I was wrong. According to the Haynes manual, there was a snap ring on the splined end of the shaft. After removing the differential cover, I realized that Haynes was also wrong. In order to avoid breaking things, I ended up taking the entire axle assembly to Four X Doctors to have them remove the shafts for me and re-gear the rear end to match the front 4.88’s. Mike at Four X later told me that the shafts came right off with some persuasion from a slide hammer. I should have taken this opportunity to replace the wheel bearings which already had 180,000 miles on them. Oh well, next time…
In order to minimize the amount of lift in the rear end, it was necessary to take the two Calmini add-a-leafs out of the spring pack. This wasn’t easy, as the through bolts holding the packs together were completely mangled and needed to be replaced. After that was done, the leafs went back in using the Calmini shackles. After sliding the axle back under the truck, I decided to leave the original spring perches in place to use as a guide when welding on the new perches. After loosely bolting the axle in place, I took my handy angle finder to ensure that the angle of the transfer case yoke matched the pinion angle. After I got the axle positioned just right, I tightened the u-bolts down, measured the angle once more, and welded the new perches in place. After reconnecting and adjusting the emergency brake, and hooking the ABS sensor up, I was about done. One small issue that I ran into unexpectedly was that my rear brake lines were way too short. Just a little flex in the rear end would have snapped the lines right off. Not a problem. After another telephone call to Indy 4x, a new set of extra long Kevlar brake lines was on it’s way.
The last item on the list was the rear driveshaft which had to be re-tubed to make up for the added height of the spring over set up. Other than measuring the distance from the transfer case flange to the pinion flange, I had nothing to do with the re-tube. Driveline Service of Bakersfield took care of that for me. After getting my like new driveshaft back, it bolted right in with no problems.
Except for the time it took to get the diff re-geared and driveshaft re-tubed, the whole rear end took less than a day to complete.
Front Driveshaft and Other Loose Ends:
Here is where the excitement of having an SAS Rodeo started waning. All the major obstacles had been tackled, however, there was still a lot of clean up work to be done. At this point, I just wanted to be finished.
One of the many little projects left to do was the front driveshaft. I decided that getting a used Toyota cv driveshaft would be the most sensible option. Using a Toyota driveshaft between an Isuzu transfer case and a Jeep front axle may sound complicated, but it worked out very well. To make it work on the transfer case end, an adaptor needed to be made to allow the Toyota flange to mate with the Isuzu transfer case flange. This was simply a large custom machined washed that took up the slack between the indents on both flanges. To start, I needed to remove the transfer case flange
cutting fenders, bump stops, brake lines, rear shocks, routing the exhaust, cutting the cross member, new mid section cross member
After I had decided that I wanted to go through with the SAS, I researched all the info I could get my hands on. The folks in the Isuzu section of 4x4wire.com were extremely helpful, and reading over many of the posts on Toyota SAS conversions at pirate4x4.com also helped a tremendous amount. At the end of my quest for SAS knowledge, I thought that I could have everything planned out perfectly to the tee. Not the case. In reality, there’s no science behind doing a solid axle conversion on an Isuzu. If you want that, buy a Toyota (those guys do have it down to a science). There’s so many different ways of doing the swap, and so many different reasons for doing it, that it will be quite awhile before we see two SAS’d Rodeos that are the same. It’s up to you to decide what is best for your ride: spring over or spring under, shackles up front or in the rear, full width or narrow…Each one has it’s good and bad points. I chose my set up based on my wheeling habits (snow, dirty trails, and some mud), and knowing that this will be the car that I’ll be driving seventy miles to work on those snowy days when the Ford Probe just won’t cut it. What I’m getting at is that my way is not the end all way to SAS a Rodeo.
A few more pointers: Get a second daily driver. This was said to me by Mike Bantz well before I began cutting and grinding. Glad I listened. After you put together a budget, double it. This is what happened to me. Sure I could have cut corners here and there, but I really wanted to get things done right the first time around. My only regret is not getting ARB’s for the front and rear – the checkbook just would allow for it.
In closing, I would like to offer my sincerest thanks to the folks who guided me through this pursuit: Matt Brown, the owner of Independent 4x, who spent many hours with me on the phone, passing on what he’s learned over the years about Isuzu trucks and axle swaps; Mike Bantz and Casey Etheredge, who took the time to reply to my many, many questions; and 4X Doctors, who weren’t afraid to give an honest opinion.
Its a small amount of fuel , but it's a whole lot of walking..Note from my Dad
97 Rodeo AKA the Pavement Princess.Maybe ill just keep it fairly stock but more capable ... And the 88 Trooper II Christine viewtopic.php?f=15&t=86504
The wild Infantryman is never truly happy in a domesticated role, though they may act like it with their stories of deployments past and the suffering they have endured.