TRE 4x4 Crab Differential Locker — Deeper Locking Depth & Nickel-Plated Gears

Step up to a stronger, more secure lock with the TRE 4x4 Crab Differential Locker. This selectable locking differential (often called a diff locker/diff air locker) delivers true 100% lock on demand, then opens for normal road manners. TRE’s Crab Locker uses developed clutch gears with deeper engagement and nickel-plated wear surfaces for durability and consistent performance, making it a robust upgrade for rocks, mud, ruts and winter traction. :contentReference[oaicite:0]{index=0}

Why choose the Crab Locker?

• Deeper locking depth — upgraded clutch gear design increases engagement depth (approx. 5 mm vs 2 mm in typical units) for a more positive, secure lock under load. :contentReference[oaicite:1]{index=1}
• Nickel-plated gears — enhanced corrosion resistance and wear life for long-term reliability. :contentReference[oaicite:2]{index=2}
• Pneumatic locker — switchable in the cab (requires onboard air) for precise, repeatable control. :contentReference[oaicite:3]{index=3}
• Wave-spring actuation — compact, resilient springing that supports smooth lock/unlock and gear strength. :contentReference[oaicite:4]{index=4}
• Oil return & leak-resistant architecture noted in third-party listings — helps prevent oil migration into air lines and reduces common leak risks. :contentReference[oaicite:5]{index=5}
• 5-year warranty and UK advice from OFM4x4.

What’s included

• TRE 4x4 Crab Differential Locker assembly
• Bulkhead fitting & nylon air line
• 12V solenoid valve
• Dash-mounted switch with wiring pigtail
• Fittings & install hardware (application-dependent)

Not included: carrier bearings/shims, gear oil, or the on-board air compressor. Add a compressor and, for dual lockers, an air manifold.

How it helps

• Off-road control: locks both wheels on an axle together for maximum traction.
• On-road manners: switches back to open diff for tight turns, parking and daily driving.
• Confidence in bad weather: assists on slippery surfaces where open diffs struggle.

Installation & setup

• Professional install recommended: set carrier bearing preload and backlash to factory spec.
• Route airlines away from heat/moving parts; pressure-test before final assembly.
• Pair with on-board air (single or twin) and an air manifold if running front + rear lockers.

You might also need

• Air Compressors — for diff locker actuation & tyre inflation.
• Air Accessories — manifolds, pump-up kits, fittings.
• Other Differential Lockers — browse more options.

FAQs

1) What is a diff locker?
A differential locker (or diff air locker) locks both wheels on an axle together for maximum traction off-road.

2) How does the Crab Locker differ?
It features deeper gear engagement (approx. 5 mm) and nickel-plated gears for improved durability and a more positive lock. :contentReference[oaicite:6]{index=6}

3) Do I need a compressor?
Yes. It’s a pneumatic locker. Use an onboard air compressor; add a manifold for multiple lockers. :contentReference[oaicite:7]{index=7}

4) Is it road-legal?
Yes. When switched off, it behaves like an open differential; engage only off-road or on low-grip surfaces.

5) What’s included?
Locker assembly, solenoid, airline, dash switch and fittings. Bearings/shims and the compressor are sold separately.

6) Will it handle larger tyres?
Yes — within the limits of your axle, gearing and driving style. The engagement depth and plating are designed for hard use. :contentReference[oaicite:8]{index=8}

7) Is it leak-prone?
Designs referenced in retailer specs highlight leak-resistant actuation and an oil return system to help protect air lines. :contentReference[oaicite:9]{index=9}

8) What’s the warranty?
TRE provides a 5-year warranty on the locker unit (see terms with your order).

Explore related categories: Differential Lockers • Air Compressors • Air Accessories