The
benefits of having a locker in one or both differentials of your Jeep are probably already obvious to you or you wouldn't be reading this article. The ability to have true 4wd in all conditions can easily be the difference between conquering the obstacle or taking the bypass. One of our latest Project Vehicles is a budget conscious build-up using a '91 Cherokee Laredo with more than 155k on the odometer. We acquired this Jeep about 6 months ago to fit the role of affordable grocery getter, kid hauler, and weekend trail warrior.
We had some fairly lofty goals for this well used Cherokee's maiden voyage.
We purchased this Cherokee in the summer of 2002 with our sights set on the Easter Jeep Safari 2003. Our very simple build-up of the XJ included lots of needed maintenance with a few simple and effective modifications. A 3" Rancho lift kit was installed followed with 31" BFG's. This obviously made a huge difference in the off road ability of our Cherokee, but it still wasn't ready for 4 rated trails in Moab. While this suspension provides surprisingly good articulation, we know we will still have wheels in the air on some obstacles. When that happens without a locker, progress has ended.
Our Cherokee came equipped with the typical Dana 35C rear axle fitted with 3.55 gears and an open differential. We didn't even have the benefit of a factory limited slip. That's fine by us though, the factory limited slip is marginal at best and still not up to any serious use. The fact that our Cherokee came with an open differential just means that it is that much cheaper and easier to install a locker. The spider gears in the stock differential case can easily be removed in favor of an EZ Locker, without the expense or hassle of setting up gear patterns, pressing on new bearings, etc. In fact, we didn't even have to remove our carrier.
The
EZ Locker for our application is part number 812A020. This part number is usually listed for Dana 35C's without ABS. Part number 812A025 is listed for use with ABS. Even though our vehicle has ABS (unfortunately the Bendix 9 system), the correct part is actually the EZ Locker for non-abs applications. The actual installation was easier than finding out which part number to use!
With
the correct part in hand, it was time to start the install. Before picking up any tools, we read, and then re-read the installation instructions. With a vague idea of how the install was supposed to go, we placed the rear axle on jack stands and removed the cover from the differential. After all of the oil was drained, we used a 1/4" combination wrench to remove the retaining bolt of the differential cross pin. Once the bolt is removed, the cross pin can be slid out of the differential case. With
the cross pin removed, slide the axle shafts inward to expose the C-clips. Remove the C-clips and push the axle shafts outward again far enough to clear the side gears. Now all of the spider gears can be removed from the inside of the case. Be sure to remove the thrust washers from the side gears as they will be reused on the EZ Locker. With the differential case empty, install both of the EZ locker side gears with the old thrust washers. Using some heavy
grease, install the steel pins in the clutch housings per the instructions. Apply more grease to the tooth area of each clutch and insert into the case. The grease will help the clutch stick to the side gears and make installation much easier. After the side gears, clutches, and C-clips are installed, align the clutches and slide the small pins into place that connect the two clutches. Insert the springs and end caps behind the pins and your installation is nearly done. We tested for proper operation per the instructions and everything was working fine. Finish the installation by reinstalling the cover and filling with gear oil (no special additives are required). Time for a test drive...
A quick spin around the neighborhood confirmed that we indeed had a functioning locker installed. The usual "click click" ratcheting sound was heard when turning corners, but overall this EZ Locker has much better road manners than the Detroit Locker that is in our 94 XJ and exhibited much quieter operation. With functionality confirmed, we were satisfied with our project and it was time to head to Utah and the 4 rated Hole in the Rock trail.
We're happy to report that the EZ Locker performed flawlessly throughout the trip. This trail would be extremely difficult if passable at all with our vehicle and open differentials. Even with just one locker installed in the rear, our Cherokee was able to negotiate the trail with relative ease. Tractech has named the EZ Locker appropriately. It makes negotiating tough trails much easier, and the entire installation only took an hour. If you have been contemplating installing a locking differential, don't hesitate any longer. The EZ Locker is super easy to install with no special tools and it's very affordable. For around $250 bucks and a little of your own labor you can enjoy true 4wd capability.
