Ultimate Dana 60s for the Ultimate Adventure UACJ-6D Jeep Build
It’s a complete natural, right? Our event is called Ultimate Adventure. Dana’s signature line of crate axles is called Ultimate Dana 60s. It’s like peanut butter and chocolate: How could we go wrong putting the two together? Especially given the fact that Dana’s first variant of its crate axle program caters to the JK Wrangler crowd with the correct width, pinion angles, and ABS, steering, and bracket systems installed to make these axle assemblies completely ready to bolt in. Builder versions with no brackets or Cs installed and with your choice of kingpin or ball joint knuckles are coming, but we think hitting the super-hot JK market first was a wise move.
We’ve been in the loop with Dana as it developed these crate axles for roughly the past 10 years, lending advice when asked and patiently waiting for the final result of many, many brainstorming meetings. But even after we suffered for almost a decade of anticipation, when they finally hit the scene there was no anticlimactic let down. These bolt-in JK axle assemblies are flat-out awesome. For starters, the front axle is a high-clearance, high-pinion design with a nodular iron diff cover. The ball-joint knuckles swing on large inner Cs that allow massive Spicer SPL-70 axleshaft U-joints. These are huge 1550-series sized U-joints that dwarf regular Dana 60-sized axle joints. The SPL-70s are housed in 35-spline 4340 nickel chromoly inner and outer axleshafts. High-quality 35-spline Warn locking hubs and a dead splindle hub design (not unitbearings) are outboard the massive Ram 2500–sized rotor and caliper package with ABS connections ready to plug in. The good stuff continues to the housing, with a ribbed centersection that helps prevent the bottom of the diff from getting hung up on rocks, super-strong 0.370-wall, 3.5-inch-diameter axletubes, and your choice of 3.73, 4.10, 4.88, or 5.38 gears with a 10-inch ring gear diameter and an Eaton ELocker or ARB Air Locker diff. And naturally, all the brackets are heavy-duty and welded in place ready to accept all your current JK linkages, and there’s a high-mount steering arm already installed on the passenger-side knuckle for lifted applications.
The rear axle is similar in many respects to the front, with heavy-duty brackets, plug-and-play ABS system, massive brake rotors and calipers, and full-floating 35-spline 4340 nickel chromoly axleshafts. Like the front, the rear features a 1350 driveshaft yoke and ribbed centersection with nodular iron diff cover. However, the rear axle features slightly thicker 0.390-wall, 3.5-inch-diameter axletubes and is a low-pinion design for additional strength. The rear runs the standard Dana 60-sized 9¾-inch ring gear but shares the same locker and gearing options as the front axle.
With Dana on board as Official Crate Axle of Ultimate Adventure, we happily ordered a pair of Ultimate Dana 60 crate axles with 4.88 gears and Eaton ELockers for our Cummins-powered build. Two large crates with “Genuine Dana Crate Axle” arrived and Tech Editor Verne Simons wasted no time in making the UACJ-6D chassis into a roller. After unboxing the Skyjacker LeDuc Series coilover suspension, shortening the JK Unlimited frame roughly 9 inches between the wheels, and setting the frame up on jackstands, Verne roughed on the Skyjacker control arms and swung the Ultimate Dana 60 axles underneath. A Yeti XD Series JK tie rod and drag link system from Steer Smarts here and a triple-master cylinder brake system from Wilwood there, and the UACJ-6D was ready for the next phase of the build, which we’ll show you next time.