The problem: Bent Jeep Wrangler JK Rubicon Dana 44 front axles. Dan McKeag, owner of Burnsville Off Road (BOR) in Burnsville, Minnesota, says that he's seeing the problem occur on axles that have been fitted with 35-inch-and-up-diameter tires that see moderate to hard trail use. As a matter of fact, he says a recent audit of trail-used JKs in his shop that are fitted with 35-inch-and-up tires showed that all had bent to some degree. In addition to the axletubes bending at the differential, the inner "C"s are bending. "It's readily apparent because you'll have gaps between the ball joints," McKeag says. "Especially on the top ball joint. You can notice a gap of up to 1/8 of an inch. You can also take a prybar and pry up on the axleshaft while it's in the Jeep and actually get the knuckle to move up and down on the ball joint." Visually you also may be able to see one or both of the front tires tilting inward at the top like in the accompanying photo.
The fix: These housings are expensive, so naturally it's best to stop the bending before it occurs. Part of the bending issue revolves around the fact that the JK Dana 44 is 5 inches wider than the TJ Dana 44, thus more leverage is put on the axle components. The bending issue has been addressed by a couple of manufacturers. As a matter of fact, Sean Holman touches on an axle gusset kit from Off Road Evolution on page 58 of this issue.
In this story we're going to take a look at BOR's new Rockproof Axle Upgrade. The full weld-on kit addresses the bending on two fronts. The kit includes a pair of axletube sleeves and six inner "C" braces. This kit has an MSRP of $295, which is a small price to pay considering the cost of just a new housing is more than $1,000. The kit is also available as gussets-only, and it has an MSRP of $125. If you want, Burnsville can install it for you. Installation runs approximately $275 for the full kit and $125 for the gussets-only. The sleeves significantly enhance the strength of the axletubes, while the gussets add considerable strength to the inner "C"s.
To install the kit it's best to pull the axle out of the vehicle, which is what we did for this story. It makes welding quite a bit easier, which can translate to better welds. It's also worth noting that this kit will fit the Dana 30 axle found in non-Rubicon JKs. McKeag says he has seen no bending of these front axles with the kit installed. "It's an easy, quick, inexpensive solution to make sure your JK front axle is going to stand up to what you're doing" he adds. "I've actually run 40- and 42-inch tires after this modification with no bending problems." Here's an overview of what it takes to install this support group of parts.
1. Here's the complete BOR...
1. Here's the complete BOR Rockproof Axle Upgrade for the Dana 44. It includes a pair of axle sleeves and six gussets.
2. The first step is to prep...
2. The first step is to prep the housing by grinding all the paint off the areas where the six gussets will be welded on. BOR technician Brian Ament spent about 45 minutes on this task.
3. It's important to install...
3. It's important to install the axle sleeves first, as welding the gussets on first can create a slight bump on the inside of the axletube and this can complicate sliding the sleeves in the housing. There are six welds used to hold the sleeves in place in the axletubes-four plug welds in the axletubes and welds on each end of the tubes. Here, Ament drills a pilot hole for one of the plug welds using an 1/8-inch bit. Then he used a 7/16-inch bit for the final hole.
4. The axle sleeves go in...
4. The axle sleeves go in next. They're machined for a perfect fit from 2-inch-diameter 0.250-wall tubing. The axle we were working on was almost new and the sleeves slid easily into the axletubes. If an axlehousing is bent this task will not be easy. It may even be impossible depending on the damage.
5. Here's how the sleeves...
5. Here's how the sleeves look installed. They're tapped in about 1/4-inch past the end of the axletube, so after they're welded they'll have a flush fit. Notice that the new sleeve is slightly thicker than the factory axletube.
6. At this point Ament welded...
6. At this point Ament welded the sleeves in place in the axletubes.
7. Here's how the end of one...
7. Here's how the end of one of the sleeves looked after being welded into the axletube.
8. The gussets went on next....
8. The gussets went on next. Each "C" gets the support of three gussets. Two are welded on the axle side and one is welded on the top of the inside of each "C." Here you can see the two axle-side gussets installed. They're made from 3/8-inch steel plate, while the inside gusset in Ament's hand is made from 3/16-inch steel plate.
9. This is how one of the...
9. This is how one of the "C"s looked with all of the gussets welded on. Even visually it's pretty clear that this is an incredible improvement in strength as compared to stock.
10. The speed sensor brackets...
10. The speed sensor brackets on each side are notched slightly around the new inside gussets so the steering radius is not affected.
11. The new gussets are then...
11. The new gussets are then painted black to match the axle and resist corrosion. The installation of the BOR Rockproof Axle Upgrade is complete.