The RCV axle kit for the JK...
The RCV axle kit for the JK includes the shafts, orange urethane boots, the boot tool, and all the necessary hardware.
If you've busted a front axle, then you know the frustration and mess of pulling the scrap metal from the end of the knuckle. Current commonly-accepted Jeep axleshaft technology is over 50 years old and the only thing that's really changed is the materials, machining process, hardening, and the size. In the end it's still the same old U-jointed axleshaft with all of its flaws. That's why we were pretty excited when RCV showed us these bolt-in axleshafts that are about double the strength of stock and eliminate many of the problems associated with U-jointed shafts.
Just How Strong?
So how strong...
Just How Strong?
So how strong are these RCV axles and joints? On an axle-snapping jig with the joints turned to 40 degrees, the stock JK U-jointed shaft spit out the U-joint and broke an ear at 3,872 lb-ft. By comparison, the RCV joint never failed, but a shaft finally snapped at 7,604 lb-ft. That's chompin' at the heels of 35-spline Dana 60 territory! For updated applications, info, and animated drawings of how the joints work, go to the RCV website.
For example, when the steering is turned, the U-joint in an axle causes the wheel to speed up and slow down several times with each rotation of the shaft. This can cause vibration and in worst cases a loss of traction, binding, and possibly shaft or joint failure. The RCV shafts feature CV joints that allow the shafts to spin at a constant velocity no matter what angle they are turned to. There is potential for more traction and less potential for failure than with U-jointed shafts. The other bonus is that the RCV joints are virtually the same strength when the steering is straight or turned. Conversely, a factory-style U-jointed shaft is significantly weaker when the steering is turned.
These aren't the same stock Birfields your Toyota buddy breaks just by sneezing on the throttle pedal. The RCV shafts and CV joints are made from high-quality aircraft steel and do not hinder the turning radius of your Jeep. Overall, the RCV JK axles are about the same strength as a stock 35-spline Dana 60 axle shaft. That's a pretty big upgrade for a simple bolt in that only takes about an hour using common hand tools. And if that wasn't enough, RCV offers a "You break it, we replace it warranty," all for about the cost of quality chromoly shafts and wiz-bang U-joints. Along with the '07-up JK Wrangler kit, RCV offers axles for the Dana 30 and 44 in TJs, the Dana 30 in YJs, XJs, ZJs, as well as a Dana 60 version. A traditional Dana 44 version should be available by the time you read this.
You'll need a 36mm socket...
You'll need a 36mm socket to remove the large axle nuts. Remove the calipers, rotors, dust shields, and unit bearings. Wire them up out of the way to avoid damage to the brake lines and ABS sensor wires. The stock axleshaft slides right out through the knuckle.
The RCV boot is placed in...
The RCV boot is placed in the knuckle from the side since it does not fit through the axleshaft window in the knuckle.
Lightly grease the splines...
Lightly grease the splines on the new shaft to keep it from damaging the seals during install. Feed the shaft through the RCV boot. You may need to insert the included tool behind the boot and use a rubber mallet to get the CV joint to fully seat inside the boot.
Smear antiseize on the stub...
Smear antiseize on the stub axle splines. It will make disassembly much easier in the future. This is especially true if you frequent mud, wet winters, and road salt.
The RCV axles come pre-lubed....
The RCV axles come pre-lubed. The grease fitting at the end of the RCV axles is one of our favorite features, though. You need a needle adapter on your grease gun to fill the joint. A few squirts of high-quality synthetic moly grease is recommended a couple of times a year.
The dust shield and unit bearing...
The dust shield and unit bearing go on just like before, only you'll need to use the included hardware that has been machined for boot clearance. A little antiseize on the threads is a good idea. Once all three (per side) unit bearing bolts are snug, torque them to 75 lb-ft.
Install the caliper and torque...
Install the caliper and torque the large caliper bracket bolts to 120 lb-ft. With a prybar or screwdriver wedged between the rotor vents and the caliper you can torque the large axle nut to 100 lb-ft.