Axle Up: 19 Ways to Add an Aftermarket Axle to Your 4x4
Axles are the legs of your 4x4. They wear the shoes and lug tons of iron across trail and tarmac alike. However, overburden these legs, and you risk them folding like the knees of an overzealous weightlifter. The benefits of upgrading your stock axles aren’t limited to safely running larger tires and wheels. The aftermarket is teeming with bombproof racing axles for high speed and heavy horsepower, factory replacement axles that slide easily beneath your rig without compromising things like steering geometry, and axles engineered for improved gear reduction and ground clearance. The task is yours to determine which combination of weight, brawn, and gearing best suits your on- and off-road needs. To make that decision simpler, we’ve gathered 19 axles from fully custom to factory replacement for you to peruse.
Spidertrax Spider 9 Pro Series Housing
The Data: Strong, secure, sexy, and complete. Spidertrax has focused on finding and reinforcing the weak points in off-road axles. The tubes are made from 4-inch-diameter, 1/4-inch-wall, heat-treated 4130 chromoly steel and will hold their own against the demands of the trails. This axle comes with a fill bung and cap, Lube Locker, and is ready for your choice of third members.
Cool Stuff: Accepts 9- and 10-inch ring gears; trim the 68-inch original length to your liking.
Currie RockJock 60VXR Full-Float Rear
The Data: This axle is designed for JK Wranglers with 40-inch rubber and V-8 power. Crafted from 3.5-inch-diameter, 3/8-inch-wall DOM tubing and stuffed with full-float 35- or 40-spline 4340 chromoly steel axleshafts, this axle is tougher than what’s under your stock rig without sacrificing weight or ground clearance. The nodular iron cover is bright red and rigid to not only keep the gears safe and add structural support, but proudly bear the Currie name badge.
Cool Stuff: A hardened steel skidplate on the bottom slides over rocks while resisting gouging and deformation.
Torq Motorsports 4-Inch Housing
The Data: Since 2011, Torq Motorsports has been building axles for anything from Jeeps to rockbouncers. The company offers mild-steel axles in three varieties: 3.5-inch-diameter, 1/4-inch-wall; 3.5-inch-diameter, 3/8-inch-wall; and 4-inch-diameter, 1/4-inch-wall tubing. The third member mounts to a faceplate that is a 1/2-inch thick for increased strength. Axlehousings are completely TIG welded and come with a 2-inch Pro Werks fill cap and bung. Torq can accommodate a variety of axle widths and can add armor, trussing, steering mounts, and more.
Cool Stuff: Check out the website for videos of these axles in action.
RuffStuff Specialties Ford 9-inch Axlehousing
The Data: Let this axle be a testament to never settling for “strong enough.” Measuring in at 72 inches, feel free to cut the 3.5-inch-diameter, 3/8-inch-wall DOM axletubes to your rig’s specifications. The 1/4-inch steel outer shell is bent 12 times for maximum reinforcement. Building a rear axle? RuffStuff will weld on a truss spanning the entire housing. This beastly housing accepts 9- or 10-inch ring gears.
Cool Stuff: Armor and axle breather fitting is optional; 100 percent human-welded—no robots.
Dana Builder Axle Program
The Data: Gone are the days of digging through the junkyard to wrestle a Dana 60 from under a decaying 4x4. Dana now offers a full line of options to build your own axle and save yourself from the rust and rat nests. Choose your front or rear cut-to-length housing, pick your gearing, then add a locker, brake kit, axleshafts, ball joint knuckle kit, and anything else from Dana’s list of goodies.
Cool Stuff: Dana and the Original Jeep Plant are both in Toledo, Ohio.
Dynatrac ProRock XD60
The Data: If you want what Dynatrac claims is the best ground clearance in the industry for this type of axle, look right here. Even though it is large enough to hold a 10.1-inch ring gear, the nodular iron centersection still clears obstacles that leave other rigs stuck, while boasting a 15 percent weight reduction. The brawniest offering features 3.75-inch-diameter, 1/4-inch-wall axletubes and will accept a full range of traction aids and gearing from 3.54 to 5.38. The differential cover is ribbed to deflect offending rocks and the 7/16-inch bolts are deeply embedded for protection.
Cool Stuff: Worried about gear oil reaching all parts of this monster? Fear not, the Dynatrac Dual Sump High Volume lubrication system makes sure every gear tooth is bathed in oil.
Dirt-Tech 4-Inch Pro Series Rear Housing
The Data: The flagship product from Dirt-Tech is designed to make your rearend strong. Axletubes are 4-inch-diameter, 1/4-inch-thick 4130 alloy and welded to the centersection, which is reinforced with two internal ribs. Optional accessories include upper three- or four-link suspension mounts, lower four-link mounts, and a top truss.
Cool Stuff: Tough enough for a 750hp trophy truck.
G2 Core 44
The Data: An aftermarket axle solution for wheelers who want something stronger than the factory, but without the cost or weight of a 1-ton axle. The Core 44 is a direct replacement for the Dana 30 found beneath ’87-’95 YJ and ’97-’06 TJ Wranglers, so all brackets work seamlessly with stock mounting points. Axlehousings feature 3-inch-diameter, 5/16-inch-wall DOM tubing, forged inner Cs, and an additionally ribbed centersection. Carrier bearing preload and backlash can be adjusted with the unique G-lock adjuster nut system. The Core 44 can be loaded with 4.10 to 5.38 gears and your choice of the ARB Air Locker, Eaton ELocker, G2 selectable locker, or Auburn ECTED.
Cool Stuff: Features cooling fins on the diff cover and skidplates on the lower control arm mounts.
John’s Industries Extreme Duty Rearend
The Data: It all starts with what are said to be the strongest die-stamped housings on the market. With 360-degree reinforced 5/16-inch-thick third member flanges and a housing stamped from 1/4-inch-thick material, the axles are ready for any on- or off-road challenge. Axletubes are 3 inches in diameter with options for 3/16- or 1/4-inch thicknesses. You can choose from 28-, 31-, or 35-spline axles to go inside your custom axletube along with options for disc and drum brakes and a variety of traction aids including Trac-Loc, Powertrax, Truetrac, Detroit Locker, or spools.
Cool Stuff: Housings can be powdercoated to your liking.
Moser Engineering C10 12-Bolt Muscle Pak
The Data: When you need an American-made, 12-bolt solution to your rearend problems, look no further than Moser Engineering. The 3-inch-diameter, 1/4-inch-wall axletubes contain 30-spline axleshafts and come completely assembled with your choice of gear ratio, brakes, traction aids, and more. The finished product can also be powdercoated to your liking.
Cool Stuff: Powdercoat colors include red, silver, orange, and black.
Trail-Gear Fully Built Rock Assault Front Axle
The Data: This axle comes loaded with shiny new parts so all you need is a rig to bolt it onto. You choose the width of your axle and Trail-Gear’s expert mechanics will add the 30-spline Birfield joints, 30-spline chromoly axleshafts, Fully Loaded Six Shooter knuckles, chromoly spindles, and heavy-duty tie rod and drag link—all so you don’t have to. Axlehousings are made with 1020 DOM 5/16-inch-wall tubing and include gusseting, an axle inspection plug at the differential, and more.
Cool Stuff: The pictured kit is for leaf spring applications, but contact Trail-Gear for three- and four-link suspension applications.
Boyce Equipment & Parts Co. 2.5-Ton Rockwell Axle
The Data: At the top of the axle food chain lies the behemoth 2.5-ton Rockwell axle. At fighting weight (without brakes) the axle weighs in at approximately 690 pounds and packs the 16-spline, 1.56-inch-diameter axleshafts necessary to turn (at minimum) 44-inch-diameter tires. The factory gearing stands at 6.72:1 with a 10.25-inch ring gear, and the axlehousing is built from 3.5x3.5-inch square tubing. Boyce offers front and rear axles in both direct-takeout and custom-built varieties, the list of goodies including Detroit or ARB lockers, pinion- or hub-mount brakes, hydraulic steering kits, and more.
Cool Stuff: Stop by the Ogden, Utah, store to see the plethora of military rigs.
Gear Tech Custom Axle Design and Manufacturing Custom Dana 60
The Data: Whether you need a custom axle for your coal-mining machine or your 4x4, Gear Tech has a solution. Pictured here is the high-pinion Dana 60 available with your choice of Yukon Gear & Axle gears, an assortment of traction devices, and disc brakes. Axles can be further customized with a variety of hubs, full-float kits, and four-link suspension bracketry.
Cool Stuff: Gear Tech’s Dana 44 front differential is claimed to be “bulletproof.”
TeraFlex JK Front Tera60
The Data: Want an extra 2 inches of suspension uptravel beneath your Jeep? TeraFlex molded the driver-side upper control arm mount to the axlehousing, allowing for extra compression and uptravel. Axletubes measure 67 inches wide and are made from 3.25-inch-diameter, 3/8-inch-wall DOM tubing. Axles come with ARB Air Lockers, TeraFlex HD ball joints, 35-spline inner and outer ’shafts, a Big Brake Kit with 13.3-inch rotors, and more. Fits two- and four-door JK Wranglers.
Cool Stuff: 580 pounds; made in the USA.
Camburg Engineering 3.50 9-Inch Axlehousing
The Data: Since 1997, Camburg Engineering has served professional racers and off-road enthusiasts alike with products deserving of the podium. The axletubes on the 9-inch housing are made from 3.5-inch-diameter, 1/4-inch-wall 4130 chromoly steel and are attached to a 3/16-inch, internally gusseted centersection. By carefully tapping the holes for third member studs instead of laser-cutting them, Camburg ensures a perfect fit to the housing. Customize your axle with centered or offset pinions, three- or four-link suspension brackets, and optional heat-treating.
Cool Stuff: The company’s website features a “Rear End Builder” to completely customize your dream axle.
East Coast Gear Supply Dana 60 High Pinion Kingpin Front Axle
The Data: The differential experts at East Coast Gear Supply take the venerable Dana 60 high-pinion centersection and build the remainder of the axlehousing to your specifications. The axletubes are made from 3.5-inch-diameter, 1/2-inch-wall DOM tubing and feature a nodular differential cover, inner axle seals, and heavy-duty kingpin inner Cs. Customizable options include gearing from Dana Spicer and Yukon Gear & Axle; pneumatic, manual, or automatic traction aids; your choice of 35-spline RCV, 35-spline 4340 chromoly ECGS, or 35-spline 4340 Yukon Gear & Axle axleshafts; and more.
Cool Stuff: Want to put a Ford 8.8 axle under your Jeep? ECGS can help with that too.
Cone Industries 3.5 Housing
The Data: Sandy Cone has been building and racing cars off-road since before the sport became an industry. The years of experience taught him the importance of strong and dependable parts. Today, Cone Industries brings Sandy’s ideas to life using the latest CAD engineering and CNC machines. Pictured here is the 3.5-inch axlehousing made from high-tensile-strength, heat-treated 4130 steel that’s fitted with emergency brake calipers. Axles can be custom-built to your specific needs with hubs, lockers, and brackets—all ready to race.
Cool Stuff: Carburized skidplates are available for all axlehousings.
Portals Anyone?Portal axles raise the centerline of the axletube above the center of the wheel, translating into gains in ground clearance. Portal axles also further multiply a vehicle’s gear reduction by transmitting power from the axleshafts into a gearbox before it reaches the wheels. Commonly found in Unimogs, the benefits of portal axles can be added to your 4x4.
74Weld Portal Box
The Data: Out with the old Unimog 404 portal axles and in with 74Weld. These portal boxes are machined from 7050 aluminum for increased strength; they add 4.25 inches of lift to the vehicle and increase the gear ratio at the wheel by 1.55:1. Options are available to adapt the portal box to solid axles and independent suspension systems.
Cool Stuff: Coming soon for JK and JL Wranglers.
Photo: John Cappa
US Gear Portal Wheel Ends
The Data: The US Gear portal wheel end is a quick way to add 4.9 inches of lift to your vehicle while also increasing the gear ratio in each corner 1.5 times. US Gear engineered this portal wheel end so you don’t have to rebuild your entire axle—the kit is made from ductile iron, fitted with 10,000-hour-life gears and bearings, and is completely bolt-on. Input shafts are 4340 steel with 35-tooth splines, output shafts are 4140 steel with 41-tooth splines, and gears are 8620 steel and 2.25 inches thick. Compatible with Dana 60, GM 14-bolt, and Ford Sterling 10.25- and 10.5-inch axles.
Cool Stuff: Adds 35 pounds per corner.