Description
Part #RD254 — ARB Air Locker Differential for the AAM 9.25″ (925/950 series) front axle, 33-spline, low-pinion (low-speed) configuration. Fits 4WD Dodge/Ram 2500 and 3500 (2007–2020) and Nissan Titan/Titan XD (2016–2019).
The ARB Air Locker RD254 is a pneumatically operated locking differential designed for the AAM 9.25″ front axle. It replaces the factory open differential carrier and delivers on-demand 100% traction without altering normal open-differential behavior when the locker is disengaged. It is built for demanding off-road conditions where standard and limited-slip differentials cannot maintain drive to both wheels.
The core technology is ARB’s pneumatic locking mechanism. When activated via the included cab-mounted switch, pressurized air engages an internal locking collar that prevents the differential side gears from rotating independently. This ties both front axle shafts directly to the ring gear, eliminating wheel spin differentiation and delivering full drive torque to both wheels simultaneously. Deactivation returns the unit to conventional open-differential operation with no driveline load or wear penalty. The system is rated for activation at any vehicle speed.
ARB’s patented timed locking mechanism governs the engagement sequence, ensuring internal components align before full lock is achieved. This produces high engagement strength while enabling fast, clean unlocking — a key distinction from mechanical automatic lockers that can generate driveline shock on disengagement. The entire operation is handled from the driver’s seat via the supplied switch and solenoid valve assembly.
The RD254 is constructed from steel using a two-piece carrier design with minimal internal moving parts for long-term mechanical reliability. The annular air seal is elastomer bonded with steel reinforcement, rated for extreme climatic temperatures at both ends of the operating range. Backed by a 5-year ARB warranty. A separate air compressor is required for operation and is not included.
Features
- Fits 2007–2020 Dodge/Ram 2500 and 3500, and 2016–2019 Nissan Titan/Titan XD — AAM 9.25″ front axle, low-pinion (low-speed), 33-spline (see fitment details below)
- Pneumatically activated locking differential — 100% traction on demand with full open-differential behavior when unlocked
- Activation rated at any vehicle speed; full control from inside the cab
- Patented timed locking mechanism for high-strength engagement and fast, reliable unlock
- Steel-reinforced, elastomer-bonded annular seal rated for extreme temperature operation
- Two-piece steel construction with minimal moving parts
- Kit includes: Air Locker differential, activation switch, solenoid valve, air line, and bulkhead fitting
- Air compressor required for operation — sold separately
- 5-year ARB warranty
- Sold individually
Specifications
| Part Number | RD254 |
| Axle | AAM 9.25″ (925/950 series) |
| Position | Front |
| Pinion Configuration | Low-pinion |
| Spline Count | 33 |
| Shaft Diameter | 1.37 in. |
| Gear Ratio | All |
| Material | Steel |
| Color | Silver |
| Warranty | 5 years |
| Compressor Required | Yes (not included) |
| Kit Contents | Air Locker differential, activation switch, solenoid valve, air line, bulkhead fitting |
Fitment
This locker fits the AAM 9.25″ (925/950 series) front axle, low-pinion/low-speed configuration, 33-spline, all gear ratios.
Vehicles covered include 2007–2020 Dodge/Ram 2500 and 3500, and 2016–2019 Nissan Titan/Titan XD across a wide range of trims and engine options (gas and diesel). See the compatibility table for the complete Year/Make/Model/Trim breakdown.
Important: Confirm your front axle is the AAM 9.25″ low-pinion variant before ordering. High-pinion AAM 9.25″ applications require ARB part #RD197 instead.