When We Heard That building an axle could now be done at home with nothing more than a metal saw, a grinder, a welder, and basic handtools, we had our doubts. In fact we still have our doubts and we've already done it! Wheelers have been narrowing axles for ages, but now you can buy the parts to build a trick lightweight axle with tough internals perfect for four-wheeling. Not only are the parts sent via UPS, but the buildup can be done at home over a weekend. This isn't a project for everyone, but if you've laid some quality welding beads in the past and if you're qualified to use a tape measure then you should consider this an option for your next trail machine. In fact it was pretty easy, and that's what has us stumped the most. We noticed a lot of competition rockcrawlers running the new Spider-9 axles from Spidertrax. We found that the lighter weight, ease of assembly (and disassembly if need be), and ground clearance of the True Hi 9 centersections were all motivations to use these axles instead of the tried-and-true Dana 60. Many of the Hi 9 attributes are equal to or stronger than the average high-pinion Dana 60. Of course most of these competitors are running lightweight buggies, so we were weary of stuffing one under something heavy like a fully armored V-8 Jeep or a fullsize truck, but the owners of Spidertrax and Hi 9 were up for the challenge, especially with the new Spider-9 housing outfitted with 31/2-inch-diameter by 1/4-inch-wall axletubes. Check out what we came up with, all by ourselves. 1. Our goal was to build a front axle at home. Luckily our home has a Miller welder, a Milwaukee chop saw, and a toolbox filled with wrenches, pliers, and hammers, and we know many of yours do too. Our calls to Spidertrax and True Hi 9 resulted in a bench full of parts including a Hi 9 third member fitted with 5.38 gears and an ARB Air Locker, a fabricated Spider-9 housing, and the Spidertrax Ultimate 60 knuckle kit.1. Our goal was to build a front axle at home. Luckily our home has a Miller welder, a Mil 2. The first step to the build is figuring out how wide an axle you want and the pinion offset. We decided to mimic a Ford high-pinion Dana 60 and shot for 691/4 inches from wheel mount to wheel mount, and we wanted to mount leaf springs at 31 inches on center, and this resulted in our pinion being about 6 inches offset from the center of the axle. Luckily Spidertrax has both an online measurement calculator and great telephone service and helped us determine where to cut the axletube so that they had the proper knuckle engagement and overall width.2. The first step to the build is figuring out how wide an axle you want and the pinion of 3. Attaching the inner "C" for the knuckle is the biggest step in the entire buildup. If not done properly, the steering geometry will be incorrect. In professional shops these inner Cs are pressed on with thousands of pounds of pressure, but we were able to pound the Spidertrax part on after just barely cleaning the tube with a sanding disk. Heating the inner C slightly with a small propane torch helped, as did a heavy hammer.3. Attaching the inner "C" for the knuckle is the biggest step in the entire buildup. If n 4. We like about 3 to 5 degrees of positive caster. This means that at ride height the top of the C is leaned back 3 to 5 degrees. Any more than 10 degrees is excessive and less than 2 is not enough. The True Hi 9 should not have a pinion angle raised over 5 degrees up from level as that could inhibit the oiling. We decided to go with 4 degrees of positive caster and 4 degrees of pinion angle; this will allow us to rock the pinion down if need be, resulting in more caster. The camber is determined by the press fit of the inner C on the tube, though we can adjust it slightly when welding.4. We like about 3 to 5 degrees of positive caster. This means that at ride height the top 5. A proper axle shop usually has a fixture that turns the housing so the welder can continuously weld. All we had was a set of jackstands and our buddy Frank the Tank who was once again cleaning out the fridge while we worked. The solution was to first tack the C in four separate points around the tube, then crank up the welder to the proper setting and burn it in with short 11/2-inch beads on opposite sides, rotating the axle so we spread the heat out around the tube.5. A proper axle shop usually has a fixture that turns the housing so the welder can conti 6. The outer knuckles use two spherical ball-and-race joints instead of standard ball joints or kingpins found in most factory axles, but are still rated at 16,000 pounds of axial load per knuckle so they should have no problem supporting a heavy trail rig. At the same time they are strong they are also light, weighing 21/2 times less than a factory Dana 60 knuckle since they are fabricated out of steel rather than heavy cast iron.6. The outer knuckles use two spherical ball-and-race joints instead of standard ball join 7. Between the ball and race and the knuckle there are various shim spacers allowing for a tight fit and future tightening of the joint should wear occur. An alignment prybar and a heavy dead-blow hammer are useful in assembling the knuckles and aligning the joints for the shoulder bolts to hold everything together.7. Between the ball and race and the knuckle there are various shim spacers allowing for a 8. The axle seals are available with a double seal and simply press into the axletube. What is neat is that they can be used with axleshafts from 27- to 35-spline sizes. We packed grease between the two seals and tapped them into place before locking them in with a set screw.8. The axle seals are available with a double seal and simply press into the axletube. Wha 9. Though Hi 9 originally designed its axle for circle-track racing, the current owners of Hi 9 realized that the axle is perfect for the off-road market since it moves the pinion up more than an inch higher than a high-pinion Dana 60. What makes these third members unique is that custom reverse-cut gears were made specifically for Hi 9 in America by Richmond Gear, and yet it can be bolted into any standard Ford 9-inch housing. In addition, two thrust blocks (aka load bolts) are added so that their tips are a miniscule distance from the back of the ring gear. In the unlikely event that the ring gear should deflect under severe load, these will keep it from flexing.9. Though Hi 9 originally designed its axle for circle-track racing, the current owners of 1 | 2 | » | View Full Article Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!