ARB Toyota 8" IFS Front Air Locker Differential - RD111, 30-Spline
RD111
The ARB RD111 Toyota 8" IFS Front Air Locker is a selectable locking differential designed for compatible Toyota 8" independent front suspension (IFS) clamshell differentials. Built for 30-spline axle configurations and 3.91-and-numerically-higher gear ratios, this air-operated locker provides fully locked front differential traction at the flip of a switch. It's an effective upgrade for Toyota Tacoma, 4Runner, and FJ Cruiser builds tackling rock crawling, technical trails, steep climbs, mud, and challenging off-road terrain where maintaining traction and steering control matters.
Unlike an automatic locker or permanent spool, the ARB Air Locker operates as a conventional open differential when disengaged, allowing normal wheel-speed differentiation during everyday driving and easier steering on high-traction surfaces. When activated, compressed air engages the internal locking mechanism, mechanically connecting both axle shafts for equal wheel rotation. The RD111 is a practical choice for Toyota IFS builds that need selectable front traction without sacrificing normal differential operation when the locker is switched off.
Includes:
- (1) ARB RD111 Toyota 8" IFS Air Locker Differential Assembly
- (1) Dash-Mounted Activation Switch
- (1) Air Solenoid Valve
- Air Line
- Bulkhead Fitting
Important: An ARB Air Compressor is required for operation and is sold separately. This locker is designed for compatible Toyota 8" IFS clamshell front differentials using 30-spline axle shafts and the specified carrier configuration. Verify axle identification, bearing dimensions, and gear ratio compatibility before ordering.
Specifications
| Manufacturer | ARB |
|---|---|
| Part Number | RD111 |
| Product Type | Selectable Air Locking Differential |
| Axle Platform | Toyota 8" IFS Clamshell |
| Ring Gear Diameter | 8.00" |
| Axle Position | Front |
| Axle Spline Count | 30-Spline |
| Shaft Diameter | 1.31" |
| Bearing Size | 53mm |
| Gear Ratio Compatibility | 3.91 & Numerically Higher |
| Differential Operation | Selectable Open / Fully Locked |
| Engagement Type | Pneumatic / Compressed Air |
| Carrier Construction | Two-Piece Steel Carrier Design |
| Material | Steel |
| Finish | Silver |
| Installation Type | Replaces Factory Differential Carrier |
| Primary Application | Toyota Tacoma, 4Runner & FJ Cruiser IFS Front Axle Traction Upgrades |
| Required Components | Compatible ARB Air Compressor, Air Supply & Differential Installation Components |
| Known Incompatibilities | Non-Compatible Toyota Differential Housings; Incorrect Bearing Sizes, Spline Counts or Carrier Configurations |
| Quantity | One Selectable Air Locker Assembly |
Fitment
Designed for compatible Toyota 8" IFS clamshell front differential applications with 30-spline axle shafts and 53mm carrier bearings. Vehicle year and model alone do not guarantee compatibility. Confirm the installed front differential housing and internal configuration before ordering.
| Make | Model | Year Range | Axle Application |
|---|---|---|---|
| Toyota | 4Runner | 2003–2023 | 8" IFS Clamshell Front Differential - Verify Configuration |
| Toyota | FJ Cruiser | 2007–2014 | 8" IFS Clamshell Front Differential - Verify Configuration |
| Toyota | Tacoma | 2005–2023 | 8" IFS Clamshell Front Differential - Verify Configuration |
Fitment Notes:
- Fits compatible Toyota 8" IFS clamshell front differential applications
- Requires 30-spline axle shaft configuration
- Designed for 53mm carrier bearing applications
- Compatible with 3.91-and-numerically-higher gear ratios
- Front differential applications only
- Requires an external compressed air supply for locker engagement
- ARB air compressor sold separately
- Not intended as a universal replacement for every Toyota 8" differential
- Verify front differential identification, bearing size, spline count, and gear ratio before ordering
- Professional differential installation and air line routing are recommended
Land Cruiser 250 Technical Note: ARB specifies replacement seal housing part number 081837SP for RD111 lockers manufactured before October 2024 when used in applicable Land Cruiser 250 configurations. Confirm the locker manufacturing date and specific vehicle compatibility with ARB before installation.
Builder Note: Toyota has used multiple front differential configurations across Tacoma, 4Runner, FJ Cruiser, and newer Land Cruiser platforms. The RD111 must be matched to the actual clamshell housing, bearing dimensions, and axle shaft configuration. Confirm these details before ordering rather than relying on vehicle model alone.
FAQ
What does the ARB RD111 Air Locker do?
The ARB RD111 is a selectable locking differential that allows the driver to switch between open differential operation and fully locked traction. When engaged, compressed air activates the locking mechanism so both front axle shafts rotate together, improving traction in difficult off-road conditions.
Will the ARB RD111 fit my Toyota Tacoma?
The RD111 is listed for compatible 2005–2023 Toyota Tacoma front differential applications. Verify that your truck uses the specified Toyota 8" IFS clamshell differential with the correct bearing size, spline count, and gear ratio configuration before ordering.
Does the RD111 fit Toyota 4Runner and FJ Cruiser models?
Yes, the supplied application information includes select 2003–2023 Toyota 4Runner and 2007–2014 FJ Cruiser models. Final fitment depends on the installed front differential configuration.
Does the ARB RD111 require an air compressor?
Yes. The ARB Air Locker uses compressed air to engage its locking mechanism. A compatible ARB air compressor and air supply system are required for operation. The compressor is sold separately.
Does the Air Locker stay locked all the time?
No. The RD111 operates as an open differential when disengaged. The driver activates the locker when additional traction is needed and disengages it when normal differential operation is preferred.
What is the difference between an ARB Air Locker and an automatic locker?
An ARB Air Locker allows the driver to select when the differential is locked. Automatic lockers engage and disengage mechanically based on driving conditions and internal design. Selectable operation provides greater control over traction and steering behavior, particularly in front axle applications.
What gear ratios are compatible with the RD111?
The supplied specifications identify compatibility with 3.91-and-numerically-higher gear ratios. Verify the installed ring and pinion gear set and carrier configuration before installation.
Can I use the RD111 for rock crawling?
Yes. Selectable front lockers are especially useful in rock crawling because they allow the driver to engage maximum traction for difficult obstacles and disengage the locker when easier steering or normal differential action is needed.
Does the RD111 include the activation switch and air line?
Yes. The supplied kit contents include the Air Locker differential assembly, activation switch, solenoid valve, air line, and bulkhead fitting. A compatible air compressor is required separately.
Will the ARB RD111 fit a Toyota Land Cruiser 250?
ARB identifies a seal housing update for applicable Land Cruiser 250 installations. RD111 lockers manufactured before October 2024 require seal housing part number 081837SP for the specified application. Confirm current ARB fitment requirements before ordering.
Does installing an ARB Air Locker require differential setup?
Yes. Installing the RD111 requires removing the original differential carrier and correctly setting carrier bearing preload, ring gear backlash, and tooth contact pattern. The air line and activation system must also be installed and tested. Professional installation is recommended.
