Skip to content

8.3 Air Lockers

ARB RD116 air-operated locking differentials for front and rear Dana 44 axles.

Model: ARB RD116 Air Locker

Axle: Dana 44, 30 spline, 3.92 & up

Front Locker Control: SwitchPros OUTPUT-17 (low-side driver, 2A)

Rear Locker Control: SwitchPros OUTPUT-10 (15A output, 2A draw)

Air Source: ARB Twin Compressor via manifold

Specifications

Spec Front Locker Rear Locker
Model ARB RD116 ARB RD116
Axle Dana 44 Dana 44
Spline Count 30 30
Gear Ratio 5.38 5.38
Solenoid Draw ~2A ~2A
SwitchPros Output OUTPUT-17 (low-side) OUTPUT-10 (15A)
SwitchPros Button Button 9 Button 10

Wiring

Solenoid Control

Locker SwitchPros Output Wire Route
Front OUTPUT-17 18 AWG Wheel well → driver frame rail → front axle (~12 ft)
Rear OUTPUT-10 18 AWG Wheel well → rear axle (~6 ft)

Wire Routing

  • Front Locker (OUTPUT-17): SwitchPros (wheel well) → along driver frame rail → to front axle solenoid (~12 ft)
  • Wire: 18 AWG (2A load, low-side driver output)
  • Protection: Split loom, P-clamps every 18", secure to frame rail
  • Rear Locker (OUTPUT-10): SwitchPros (wheel well) → to rear axle solenoid (~6 ft)
  • Wire: 18 AWG (2A load)
  • Protection: Split loom where exposed, secure to axle housing

Air Line Routing

Air Line Installation

Air lines from manifold must be routed to both axles with proper protection from heat, abrasion, and road debris.

Line Route Length
Front Locker Manifold (under seat) → along driver frame rail → front axle ~12 ft
Rear Locker Manifold (under seat) → to rear axle ~6 ft

Air Line Specifications:

  • Type: ARB air line kit (1/4" OD nylon tubing, 200 PSI rated)
  • Fittings: Push-to-connect fittings at manifold and locker ends

Protection:

  • Split loom over entire run where exposed to road debris
  • P-clamps every 12" along frame rail
  • High-temp silicone sleeve where crossing near exhaust (6" minimum clearance)
  • Rubber grommets at body/frame penetrations

Operation

Engagement Sequence

Front Locker:

  1. Press Button 9 (OUTPUT-17)
  2. Solenoid opens, pressurized air from tank → front locker
  3. Front differential locks instantly (no waiting for compressor)
  4. Release Button 9 to disengage

Rear Locker:

  1. Press Button 10 (OUTPUT-10)
  2. Solenoid opens, pressurized air from tank → rear locker
  3. Rear differential locks instantly
  4. Release Button 10 to disengage

Automatic Refill:

  • After multiple locker uses, tank pressure drops below 135 PSI
  • Pressure switch automatically activates compressor to refill tank
  • No user action required

Safety Considerations

Locker Operation

  • Only engage lockers at low speeds (typically <5 mph)
  • Disengage lockers before returning to normal speeds
  • Never engage lockers on dry pavement
  • Ensure adequate air pressure before engaging lockers

Outstanding Items

  • Verify ARB RD116 compatibility with Dana 44 30-spline 5.38 gear ratio
  • Order ARB air line installation kit with 1/4" fittings for front/rear lockers