Project Redneck: Talking Gears & Lockers With Motive Gear & Eaton

Jeep differentials – love ’em or hate ’em, you can’t get rid of ’em. Sooner or later, every diff finds its breaking point, and the stock Dana 35 rearend and Dana 30 front end on Project Redneck were not suited to hardcore rockcrawling.

After taking care of Redneck’s other areas – including lift, windshield, beadlocks, bumpers, and more – we felt ready to tackle the drivetrain. This was actually a really good time, since we had added a great deal of weight to the Jeep, and needed the right setup to keep it all movin’ and groovin’.

This was how we got to talking with Eaton and Motive Gear; Eaton, for its E-Locker and Detroit Locker, and Motive Gear, for its 5.38:1 ring and pinions. These crucial components would be hidden inside the new Dana 44 axle housings going onto Redneck, but they were definitely worth examining first.

Background Of The Parts

Left to right: The Eaton E-Locker, Eaton Detroit Locker, and Motive Gear 5.38:1 ring and pinions.

At the core of these parts is the desire for traction. On top of that, it must be transmitted in the most efficient manner to the front, back, left, and right.

However, just like de-furring a feline, there are many ways to get to this point. We spoke with Eaton’s Barney Gwozdz to learn the ins and outs of the E-Locker and Detroit Locker. In doing so, we learned how these items worked, and what made them a good combination for Project Redneck.

The Detroit Locker shares its internals with the older Detroit NoSpin differential, which debuted in the 1940s.

“The main difference between the E-Locker and Detroit Locker is in activation,” said Gwozdz. “The E-Locker is a selectable electric locker, where you turn it on or off. It’s either fully locked, like a spool, or it’s open, like a standard differential. The Detroit Locker, on the other hand, is a mechanical locker. It’s automatically locked at all times until you go into a turn. Without heavy torque input, it allows the outside wheel to rotate independently of the inside wheel.”

Both the E-Locker and Detroit Locker are tried and true units in this day and age. “The Detroit Locker, which was created for street vehicles, evolved from the Detroit NoSpin, which arrived in the 1940s for semi trucks and earth-moving vehicles,” said Gwozdz. “They have the same internal workings, but are intended for different applications.”

The E-Locker’s electronic operation allows it to activate and deactivate with the flip of a switch. This makes it ideal as a rearend differential, whereas the Detroit Locker’s mechanical operation is better suited to the front axle.

The E-Locker, meanwhile, was a more recent Eaton invention. “The E-Locker was created for the AM General HMMMV,” explained Gwozdz. “From that, we expanded our portfolio and changed the design to be more robust for hardcore off-road use.”

Speaking of off-road use, both the E-Locker and Detroit Locker are well-suited to the purpose. “Limited-slip differentials rely on some sort of rolling resistance on each of the wheels for them to function,” said Gwozdz. “Locking differentials have the ability to lock both wheels under any conditions, whether they’re up in the air, or moving through mud. That makes them great for off-roading, where the terrain can be slippery.”

Using a Detroit Locker up front and E-Locker in the back makes sense for Project Redneck and its off-roading expectations. "In this case, the terrain you're dealing with on the West Coast warrants a lot of maneuvering," said Gwozdz. "Having a mechanical locker on the front and a selectable locker in the back makes the most sense."

Working in conjunction with these Eaton lockers are Motive Gear’s 5.38:1 ring and pinion. These replace the stock ring and pinions that were in the Dana 35 and 30, back before we swapped out housings to the Currie RockJock 44s.

Motive Gear’s 5.38:1 ring and pinions for the Dana 44. To see why and how we approached swapping from the stock Dana 30 and 35 axles to Currie RockJock 44s, see this article.

Motive Gear’s Eric Filar explained what folks should consider before choosing a gear ratio. “The first thing the end user needs to consider when choosing their new gear ratio is how they intend to use the vehicle,” he said. “If it’s used primarily on-road as a commuter, a slightly higher, numerically lower, gear ratio may be preferred for better fuel mileage. If the vehicle is used primarily off-road, a deeper gear ratio to help increase its performance in the dirt may be the better option, but may sacrifice fuel mileage due to higher cruising RPMs.”

This tied well into Project Redneck, which was going to be a dedicated rockcrawler in the end. This was why we went from the stock 4.10:1 ratio to a “taller” ratio of 5.38:1. For every 5.38 teeth on the ring gear, there was 1 tooth on the pinion gear. It would mean a lower top speed on the Jeep, but a benefit to low-end torque, which is what we want on this Wrangler.

With 5.38:1 gear ratio ring and pinions, Project Redneck will trade top speed for better low-end torque. This is an ideal trade-off for what will become a dedicated rockcrawler.

Of course, it would all be for naught if the quality wasn’t up to snuff on these ring and pinion sets. Thankfully, Filar put those fears to rest: “We use technologically advanced manufacturing processes coupled with high-level, in-house QC. Our staff is made up of enthusiasts constantly looking to improve our recipes. Also, we use every form of motorsports racing to test new and existing products – Top Fuel drag cars, Ultra4 rock racers, Trophy Trucks, and more.”

Armed with these drivetrain treasures, Project Redneck stands to become our resident, radical rockcrawler that we’ve always dreamed of. Stay tuned for the installation, and check out more on Eaton and Motive Gear online.

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About the author

David Chick

David Chick comes to us ready for adventure. With passions that span clean and fast Corvettes all the way to down and dirty off-road vehicles (just ask him about his dream Jurassic Park Explorer), David's eclectic tastes lend well to his multiple automotive writing passions.
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