Click for Coverage
Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM
  • JP Magazine
  • Dirt Sports + Off-Road
  • 4-Wheel & Off-Road
  • Four Wheeler

The New ELocker from Eaton

Posted in How To: Transmission Drivetrain on October 1, 2009
Share this

Until recently, there hasn't been much in the way of selectable electric lockers outside of OEM applications. A couple of years ago there was the Detroit Electrac, but the unit was overly-complicated and proved less than durable in Jp's long-term testing. Eaton must've agreed because a short time after it bought the Detroit brand, it yanked the Electrac from its product line. Thankfully, Eaton has lots of experience producing electronically selectable lockers for OEM applications, like GM's gold-chainer Hummer H2 and others. So it didn't take much for the company to lock its engineers in a candle-lit room and pelt them with melon balls until they came up with a viable design for the aftermarket that didn't require air lines, a compressor, or super-long lengths of cable to operate.

What they came up with is Eaton's new ELocker. But don't think it's simply a fluffed and repackaged version of some OEM application. Nope, these are stronger. Take for example the lowly Jeep Dana 30 and Dana 35 application we got our hands on for our testing. Rather than two-pinion cases, these are four-pinion (C-clip axles are three pinion). And each unit features forged gears, hardened lock pins, and a solid nodular iron case. Simply put, when properly operated, these lockers are nowhere near being the weak link in your Jeep's axle assembly. Eaton says only engage and disengage the locker at speeds below 3mph to avoid damage and don't exceed 20mph with the unit locked. Simple enough.

Because we were already running a Superior Axle & Gear Super 35 kit in our Wrangler's rear Dana 35, we ordered up a 30-spline ELocker for the rear. And although the ELocker is available in the stock 27-spline for the front Dana 30, we plan on keeping this front axle as long as possible, so we ordered a 30-spline ELocker for the front and took the locker install as an opportunity to upgrade to Superior's superb 30-spline Evolution Series axle shafts. We brought the whole mess o' parts down to TAG Motorsports in Escondido, California, where our buddy Jay Miller did the install to our exacting standards.

So, how do we like 'em? In a word, they're great. On the street it's so sweet to have open diffs once again. With absolutely no handling drawbacks on the road, it's also a great bonus to have an electric spool at the flip of a switch. The ELockers come with a complete wiring harness, relay, and illuminated rocker switch. Our normal method of operation is to line up at our obstacle and engage the locker(s) when stopped or at a slight roll. The ELockers engage crisply and with no hint of delay. Occasionally we noted the front didn't seem to unlock quite as readily if we disengaged the locker with the wheels turned or while the drivetrain was still under load, but simply depressing the clutch or waiting until the wheels were straight allows the locking pins to disengage from their bores and unlock the locker. So far it's been a smooth, trouble-free experience.

With a Superior Super 35 axle upgrade and truss already in the Jeep's Dana 35 rear axle and the new Superior Evolution Series shafts in the front, our Jeep's factory axles are about as strong (and expensive) as they can be. The ELockers are a welcome improvement to this Jeep's on-road persona and have proven themselves both on- and off-road in the six months of testing we've put on them thus far.

The stator assembly (shown in hand) must be removed to install the ring gear. It simply slides off once the snap ring is removed. Also, both the Dana 30 and Dana 35 applications use different carrier bearings and races than factory. Both use PN LM102949 bearings and PN LM102911 races. It's also highly advisable to use setup bearings to dial in the backlash because some bearing pullers may damage the stator assembly.

The ELocker install requires a 1/2-inch hole be drilled in the diff for the wiring grommet to poke through. You could technically punch a 29/64-inch hole through the diff cover, but the thinner sheetmetal cover gives the grommet less sealing surface, increasing the potential for leaks.

To dust off an old chestnut, here's the beef. In this exploded view you can see from right to left the electromagnetic stator assembly which, when energized by a source of 12V power, engages the ramping mechanism and pushed the locking pins into bores, thus locking the side gear to the opposite side of the case. The four-pinion design, exceptionally high-quality components, and exacting machining tolerances make this one helluva strong locker.


Superior Axle & Gear
Rancho Cucamonga, CA 91730
Cleveland, OH 44114
Tag Motorsports
Escondido, CA 92029

Connect With Us

Newsletter Sign Up

Subscribe to the Magazine

Browse Articles By Vehicle

See Results