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These two get cross-shopped constantly, but they are not the same kind of part. The Eaton ELocker (and the newer four-pinion ELocker4) is a selectable locker: an open differential until you energize a 12-volt electromagnetic coil, then a full lock. The Yukon Grizzly Locker is an automatic full-carrier locker: locked under power, with a ratcheting mechanism that lets the outside wheel overrun in a turn and then re-engage.
Short version from the bench: if the vehicle is a daily driver, or the locker is going in a front axle, the ELocker is usually the right call. If it is a rear axle on a truck that wants a simple, no-wiring, always-ready locker and the owner can live with the noise and manners, the Grizzly makes a lot of sense, especially in heavy axles.
How Each One Works
Eaton ELocker / ELocker4
Inside the case is a stator coil and an armature. When the switch sends 12 volts to the coil, the magnetic field pulls the locking mechanism into engagement and ties the side gears to the case, so both axle shafts turn together. Kill the power and springs pull it back out. Switched off, it is an open diff in every way that matters: same steering feel, same tire wear, same quiet operation as stock.
Yukon Grizzly Locker
The Grizzly replaces the entire carrier. There is no switch. Under drive torque both wheels are locked together. When one wheel needs to go faster than the other, like the outside tire in a turn, the ratchet teeth separate and let it overrun, then snap back in when the speeds match. It is always on. You do not decide when it locks; the driveline does.
Side-by-Side Comparison
| Factor | Eaton ELocker / ELocker4 | Yukon Grizzly Locker |
|---|---|---|
| Type | Selectable, electric (12V coil) | Automatic, full carrier |
| Street manners | Stock, open diff when off | Clicking, clunks on throttle changes, some push in turns |
| Tire wear | Normal when off | Can increase, especially on short-wheelbase rigs |
| Front axle | Good choice | Generally not recommended for anything driven on the street |
| Rear axle | Good choice | Good choice if you accept the manners |
| Wiring | Required: switch, relay/fuse, harness through housing | None |
| Typical failures | Coil/stator/armature, chafed or broken wiring | Worn ratchet teeth, increasing noise |
| Field service | Service kits available (stator/armature, electrical) | Usually replaced as a unit |
| Install | Carrier swap + gear setup check + wiring | Carrier swap + gear setup check |
Street Manners: Where the Decision Usually Gets Made
This is the part people underestimate. An automatic locker is a different driving experience. In a parking lot you will hear ratcheting as the outside wheel overruns. On and off the throttle in a turn, it can bang as it re-engages. Short-wheelbase rigs feel it more than long trucks, and wet or icy roads make it worse because the rear can step out when both wheels drive at once under power.
The ELocker sidesteps all of that. Switched off, nobody can tell it is there. That is the whole point of a selectable: you get open-diff behavior 95 percent of the time and a full lock for the 5 percent you need it.
Trail Performance
Locked, a locker is a locker. Both give you a hard 50/50 split, and on a rock ledge or a cross-axle hole you will not feel a difference. The Grizzly's advantage is that it is always ready. You never forget to flip a switch, and there is no wire to rip off on a rock. Its disadvantage is that in tight, off-camber turns on the trail you cannot unlock it to make the turn easier, and on slick side-hills a locked rear wants to push the back end downhill.
The ELocker's advantage is control. You can run open for tight switchbacks and slick off-camber sections, then lock only where you need it.
Front Axle vs Rear Axle
This is the clearest line in the whole comparison. An automatic locker in a front axle makes steering heavy when the front is engaged, and the truck tends to push straight ahead in turns. On anything driven daily in 4WD, or on an IFS truck, we do not recommend it. Put a selectable up front.
That is why the ELocker4 is popular in Dana 44 front axles and Toyota 8-inch fronts, and why you see the Grizzly mostly in rear axles like the Dana 60 and the GM 14-bolt.
Front-axle selectables: ELocker4, Dana 44 front, 30-spline, 3.92 and up · ELocker4, Toyota Tacoma / Sequoia / Tundra / T-100, 30-spline
Wiring and Switch Requirements
The ELocker needs a dash switch, a fused circuit (a relay is good practice), and a harness that exits the axle housing through a sealed pass-through. That harness is the number one thing we see go wrong. It gets routed too close to the driveshaft, the exhaust, or a suspension link, the insulation rubs through, and the locker quits working. Route it high, loom it, and leave slack for full suspension travel.
The Grizzly needs nothing. No switch, no wire, no air. For some owners that alone settles it.
Failure Modes
ELocker
- Coil, stator or armature failure. Locker will not engage, or engages intermittently. Check voltage at the axle first; most "dead" lockers are wiring.
- Chafed or broken harness. Covered above. Cheap to fix, annoying to find.
- Field fixable. Eaton sells service kits, so a failed stator does not mean a new carrier: ELocker service kit, Dana 30/35 · stator/armature kit, Dana 44 four-pinion
Grizzly Locker
- Worn ratchet teeth. Rounded teeth mean more noise and harder engagement.
- Noise that gets worse with time. Some noise is normal. A locker that has gotten much louder than when new is worth pulling and inspecting.
Install Complexity
Both are full carrier swaps. The ring gear comes off the old case and bolts to the new one, so you are setting carrier bearing preload and backlash and checking the pattern. Pinion depth does not move, but this is still a gear setup job. The ELocker adds drilling or using the housing pass-through, plus switch and harness work. Neither is a driveway job for someone who has never set backlash.
Cost
Locker prices vary a lot by axle, spline count and ratio range, so compare the exact part numbers for your axle. As a rule the Grizzly is the cheaper box, and the ELocker costs more once you add switch and wiring.
Who Should Buy Which
Buy the ELocker if: it is a daily driver, it is going in a front axle, you drive in snow and ice, or anyone else drives the vehicle. Jeep JL with a Dana 35 / M200 rear is a common upgrade: ELocker for JL Dana 35 / M200, 29-spline.
Buy the Grizzly if: it is a rear axle, you want zero wiring, the rig is a dedicated trail or work truck, and you can live with the noise. Heavy rear axles are where it shines:
Need Parts? Ships Same-Day
Lockers, service kits, and the bearings and seals you need for the carrier swap. Driveline and transmission hard parts are also available through our sister store CoreTransmissionParts.com.
Shop Gearbox Insider →FAQ
Can I run a Grizzly Locker in the front axle?
You can, and some dedicated trail rigs do, but on a vehicle that drives on pavement in 4WD or has a locking front hub setup that stays engaged, an automatic locker up front makes steering heavy and the truck push straight in turns. For a front axle we recommend a selectable locker like the ELocker4.
Does an ELocker work like an open differential when it is switched off?
Yes. With the coil de-energized the ELocker behaves like an open differential, so street manners, tire wear and steering feel are the same as stock. It only locks when you flip the switch and the coil gets 12 volts.
Why does my automatic locker clunk and click in parking lots?
That is the locker doing its job. When one wheel has to travel farther in a turn, the ratcheting mechanism lets it overrun and re-engage, which makes clicking and the occasional bang on throttle changes. It gets worse with worn teeth, light vehicles, and short wheelbases, but some noise is normal for any automatic locker.
Do I need to reset gear pattern when installing either locker?
Both are full carrier replacements, so the ring gear moves to a new case. Pinion depth does not change, but you have to verify backlash and carrier bearing preload and check the pattern. Treat it as a gear setup job, not a bolt-in.