Ali Mansour
Brand Manager, 4WD & Sport Utility
If you’re looking to take your 4x4 on more serious adventures, then you’ll likely want to trade in your open differentials for a set of lockers. With the exception of a few well-equipped rigs such as the Ram Power Wagon and Jeep Wrangler Rubicon, most 4x4 SUVs and pickups come from the factory with open differentials. An open differential is a carrier that is fitted with a set of free-flowing spider gears. When throttle is applied the open differential sends power to the wheel with the least resistance, which usually means the tire with the least traction.
To get both wheels spinning at the same speed, you’ll need to upgrade to a locking differential. A differential locker works by engaging the differential carrier’s internals so the axleshafts become “locked.” Locking the axleshafts allows both tires to bite for traction and aids you greatly when wheeling in loose and challenging terrain.
Drop-in lockers require the use of an open differential carrier. A standard open carrier uses spider gears to allow the axleshafts to rotate freely and at different speeds. Be sure to double-check that your carrier is in good shape (free of cracks) and it’s actually an open carrier. To the untrained eye some OE-style limited slips may appear to be open, but they are not and will not work with the Lock Right or Powertrax.
There are dozens of locker options, some more expensive than others. When it comes to affordable, installer-friendly, effective lockers, Richmond Gear’s Lock Right and Powertrax series lockers are at the top of the list. Both brands of lockers are automatic, which means they automatically “lock” when powered is applied. They are commonly referred to as lunchbox or drop-in lockers, as they drop in place of the spider gears inside of an open differential carrier. One of the key benefits of drop-in style lockers is that you don’t have to change out your stock open differential carrier, nor do they require any high-dollar specialty tools to install.
To put a set of these installer-friendly lockers to the test, we called up the differential experts at Just Differentials and ordered a Dana 30 front Lock Right locker and a Dana 44 rear Powertrax locker. Just Differentials carries a wide array of gears, lockers, and even complete axle assemblies and can help inform you with many of the pros, cons, and basic information you’ll need when upgrading your differentials. We had our locker set installed in our ’04 Jeep Wrangler Unlimited in an afternoon. If you have a little wrenching experience and a solid tool set, we’re glad to say that this is an easy driveway install.
A right-angle pick along with some automotive grease is a must to set the springs in both the Lock Right and Powertrax. Notice we removed both of our carriers along with the ring gears from the differentials. Depending on the application you can actually drop in the lockers with the differential still inside of the housing.
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Rocking & Locking
Installing a front and rear locker in your 4x4 is one of the most instantly noticeable and worthwhile investments you will ever make. No matter how extreme the terrain or twisted your suspension gets, each tire will continue to pull, even if one or all become airborne. Admittedly the lunchbox lockers we installed here are not without their drawbacks. On the road the rear locker sometimes creates quirky handling and often chirps tires when maneuvering around tight places (parking lots or slow and sharp turns in the city). They also make a clicking or ratcheting sound from time to time. Overall, the pluses of the lockers outweigh the minuses. For the value, ease of installation, and outright performance, the drop-in lockers are a sound investment for wheeling enthusiasts looking to take their rig to the next level.
