Harrop Eaton E Locker: The Push-Button Traction Upgrade Every 4WD Needs
- Nick Flanigan aka The Mindful Mechanic
- Nov 28
- 3 min read
When you are off-road, traction is everything. One patch of loose rock, one muddy rut, one off-camber climb—and suddenly your open diff is sending all your power to the wheel with zero grip. This is exactly why selectable lockers exist… and why the Harrop Eaton ELocker has become one of Australia’s most trusted traction upgrades.
Here at Opposite Lock Sunshine Coast / TGR HQ, we install and recommend Harrop ELockers because they are strong, reliable, Australian-engineered—and built for real off-roaders who expect more from their rigs.
What Is a Harrop Eaton ELocker?
The Harrop Eaton ELocker is an electromagnetically activated locking differential. Unlike traditional lockers that rely on air compressors and airlines, the ELocker uses a simple push-button system to instantly lock your differential.
✔ No airlines
✔ No compressors
✔ No delays
✔ No complexity
Just pure traction, on demand.
When disengaged, it behaves like an open differential. When engaged, it becomes a full locker, sending 100% of available torque equally to both wheels on the axle even if only one wheel has traction.
Why Off-Roaders Love the ELocker
1. Instant Push-Button Traction
When you activate the system, a small 8-amp current energises an electromagnet that engages the locking mechanism. The response is almost instantaneous, giving you grip exactly when you need it.
2. Zero Air, Zero Hassle
No compressors. No air lines. No waiting for pressure to build. No failure points from leaks or broken fittings.
This is one of the biggest advantages of the ELocker over pneumatic systems.
3. Built Strong with Forged Gears
Harrop builds the ELocker using precision-forged gears—not cut gears—creating:
superior strength
longer service life
better durability under load
This is the exact reason Harrop is trusted by OE manufacturers and military-grade applications.
4. Military-Grade Engineering
The ELocker was originally developed with Eaton Corporation for use in US military vehicles. Harrop then partnered with Eaton to engineer a full range of ELockers specifically for the harsh Australian off-road environment.
You get world-class engineering made right here in Melbourne, Australia.
5. Tested to Extreme Conditions
Harrop’s in-house torture testing proves the ELocker’s durability.
In their stress test on a Nissan Patrol rear axle, they applied over 10,000 Nm of pinion input torque until the axles broke.
The ELocker? Still perfect.
That’s the kind of reliability you want when you are halfway up a rocky climb with no recovery vehicle in sight.
How the Harrop ELocker Works (In Simple Terms)
Here’s what happens when you hit the switch:
An electromagnet inside the diff housing activates.
The friction between the armature and magnet moves a set of locking pins.
The lock ring engages with the side gear.
Both axle shafts are forced to rotate together.
You get full, equal torque to both wheels.
It's simple, clean, and tough designed for the real-world terrain Aussie drivers tackle every weekend.
Forward or Reverse? The Locker Stays Engaged
A common myth says ELockers drop out when switching from forward to reverse.
The truth? They stay locked as long as torque is applied.
In extreme conditions—or when you are trying to back out of trouble the ELocker stays engaged and keeps delivering traction.
Why Choose Opposite Lock Sunshine Coast / TGR HQ?
At TGR HQ, we live and breathe off-road culture. Our workshop is run by second-generation mechanical specialists who build, race, test and wheel these products in real conditions—not just on paper.
When you book your install with us, you get:
✔ Qualified 4x4 mechanics
✔ Clean wiring + neat switch installs
✔ Correct diff setup and backlash
✔ Genuine Harrop components
✔ Full traction setup and testing
✔ Peace of mind on every track
You want a locker you can trust.
You also want a workshop you can trust to install it properly.
That’s us.
Comments