By Christian Sturtz, [email protected]
Photos by Christian Sturtz
When it comes to older vehicles, traction device options are limited. You can get about anything for late-model vehicles – electric, air, mechanical, and drop-in options are all available. I wanted to do something with my 1949 CJ3a, but for the old stuff, the pickings are slim. I knew PowerTrax still made a Lock-Right for the Dana 25/27 ten spine axles and the 41/44 ten spline axles. The Lock-Right looked like a great option for this project. Traction devices provide more equal power to both tires on a single axle; they come in handy when you go into an off-camber river bottom or up a steep climb. Two of the wheels will have less weight on them, and with standard open diffs, those will be the ones that get the power. Traction devices keep you moving even with tires off the ground. (Figure 1)
I started by putting the Jeep on stands and removing the tires. I then ran the brake adjusters back, removed the rear drums and axle nut, and put a puller on to remove the wheel hub. *Tip: be careful if you use one of these pullers; when the hub pops loose, it may fly with the wheel hub several feet and could hurt you or someone else. Next, I removed the cover, drained the axle housing, and removed the bolts and nuts in the axle flange. The backing plates, along with shims and bearing retainers, were removed. If careful, you won’t have to unhook the brake lines to remove the backing plates – just don’t kink them. The axle shafts were then slid out a few inches to remove the carrier. (Figure 2)
The carrier can now be unbolted and removed. Make sure the caps are marked before taking the carrier out. With the carrier on the bench, I decided to mark the ring gear location; this gear has been in the same spot on this carrier for over 70 years; no need to start new problems this late in the game. Next, the keepers were pounded flat, bolts removed, and ring gear slid off the carrier. The pin (through the cross shaft) was tapped out with a punch and removed along with the axle spacer. The gears were also rolled out of the carrier and removed. Be sure to keep the thrust washers off the side gears and the axle spacer because they will be reused (the axle spacer is only on the rear end). I ran into a couple of issues, I had an oversized egg-shaped thrust washer on one side, and the ring gear bolts were in bad shape. I had to take apart an AMC 20 carrier to rob a couple of thrust washers- thankfully, they measured out very close. (Figure 3) I will use new Dana 30/standard 44 ring gear bolts on the reassembly with thread lock and no keepers.
For the assembly/installation of the locker, I applied grease to all the parts and laid them out. I took the thrust washers and slid them on the journals of the couplers. Next, I put one of the couplers in the bare case. Then I assembled the driver and sat it on the installed coupler. An assembled driver consists of a driver, a driver with sheer pins installed, and a spacer in the middle of the coupler. Be sure to put the sheer pins in the large window hole. This process is repeated for the other side of the carrier. (Figure 4)
To complete the rear install, the axle spacer must be dropped down through the axle shaft hole, and the new cross pin slid through it. The cross pin must be retained with a pin. The directions have you put the bias springs in before the cross pins, but I find it easier to line things up when the cross pin is installed. Check for the correct gap between the pin and the spacer. I also chose to put the springs in last because they are hard to remove without damaging them and have a high likelihood of flying across the shop. (Figure 5)
In my application, I had to trim some off the end of the new cross pin because it stuck past the carrier and wouldn’t allow me to install the ring gear. After replacing and torquing the ring gear bolts, I reinstalled the carrier. On these old housings, the bearing cap bolts stick through the back of the housing, so use sealant on the threads to prevent an oil leak. Torque the bearing caps and fill the axle with the correct oil. The rest of the axle goes back together in the reverse order it was taken apart. (Figure 6)
The front axle has almost an identical procedure as the rear, except the front differs a little in tear down. (Figure 7) With both front and rear ends done, it is time to try it out. What a difference! I can creep where I couldn’t before – Lock-Right may be the right choice for your next vintage project.
Parts:
PowerTrax
- Lock Right 2110-LR
- Lock Right 2415-LR
Sources:
PowerTrax
Midwest Truck & Auto Parts (Ten Factory/Motive/PowerTrax)
1001 W. Exchange Ave.
Chicago, IL 60609
1-800-934-2727
