Description:
ARB has been challenging conventional thinking on off road equipment designs for over 30 years, and the ARB Air Locker has been a success from the very beginning. Created to provide 100% traction on demand, without sacrificing any of your vehicle’s highway driving performance, ARB Air Lockers employ a 12 volt air compressor designed to activate (and deactivate) a solid and durable locking mechanism inside the differential. This gives you the traction you need, when you need it, all at the flick of a switch, all within the safety and comfort of the driver’s seat.
The advantage of the ARB Air Locker lies in the pneumatically operated locking system inside the differential. When activated, the Air Locker prevents the differential gears from rotating and therefore prevents the axle shafts from turning independently of each other. With both wheels tied directly to the rotation of the ring gear the vehicle maintains maximum possible traction at all times. When unlocked, it operates just like conventional "open" differentials.
In addition to providing outright improvements to a 4x4’s off road capabilities, the Air Locker offers significant environmental benefits. When approaching difficult terrain, less reliance is put on momentum. An Air Locker equipped truck can be driven in a slower, safer and more controlled manner as a result of vastly improved traction. This style of driving greatly reduces the likelihood of incurring vehicle damage and lessens the environmental impact as well.
Select tabs below for product description.
- Front Lockers
- Rear Lockers
| Range Rover |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
To 93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-98 |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD138 |
98-06 |
Rover Type, P38A |
31.5 (1.24") |
24 |
3.54 |
| |
| Discovery |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
To 93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-98 |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Discovery II |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD128 |
All |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Defender 110, 130, County |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
83-93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-Up |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Defender 90, County |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
84-93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-Up |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| |
| LWB Models V8 Engine |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
79-83 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD20 |
79-83 |
Salisbury Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Series III, Series II, Series I |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
48-85 |
Rover Type |
28.2 (1.11") |
10 |
4.70 |
| ARB-RD32 |
48-85 |
Salisbury Type |
31.5 (1.24") |
24 |
4.70 |
| Range Rover |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
To 93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-98 |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD128 |
98-06 |
Rover Type, P38A |
31.5 (1.24") |
24 |
3.54 |
| |
| Discovery |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
To 93 |
Rover Type |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-98 |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Discovery II |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD128 |
All |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD138 |
02-Up |
Rover Type, P38A |
31.5 (1.24") |
24 |
3.54 |
| |
| Defender 110, 130, County |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD20 |
83-02 |
Salisbury Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD128 |
02-Up |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD138 |
02-Up |
Rover Type, P38A |
31.5 (1.24") |
24 |
3.54 |
| |
| Defender 90, County |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
83-93 |
Rover Type, 4 Cyl |
28.2 (1.11") |
10 |
3.54 |
| ARB-RD128 |
93-Up |
Rover Type |
31.5 (1.24") |
24 |
3.54 |
| ARB-RD138 |
02-Up |
Rover Type, P38A |
31.5 (1.24") |
24 |
3.54 |
| |
| LWB Models V8 Engine |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD20 |
79-83 |
Salisbury Type |
31.5 (1.24") |
24 |
3.54 |
| |
| Series III, Series II, Series I |
| Part # |
Year |
Description |
Shaft Dia |
Spline
Count |
Ratio |
| ARB-RD127 |
48-85 |
Rover Type |
28.2 (1.11") |
10 |
4.70 |
| ARB-RD32 |
48-85 |
Salisbury Type |
31.5 (1.24") |
24 |
4.70 |
|
Notes:
- If vehicle was manufactured during 1993, check spline count
- Air Locker not available for vehicles equipped with high load option
- RD03A ring gear spacer required. Longer ring gear bolts (not supplied) are also necessary - (Land Rover part no. 576521)
- When an RD03 Air Locker is to be installed in Range Rovers manufactured prior to 1980 (approx.), special carrier bearings
- (No. K11300/K11162) may also be necessary - Land Rover part no. RTC3426
- Some vehicles have crown wheel bolts which cannot be reused and must be replaced. Consult service manual
- P38A was not used on North American delivered Discoverys - use RD56 |