ARB / Driveline & Steering

ARB RD157 Air Locker | JK Rubicon 35-Spline Upgrade

Check vehicle fitment
£1,040.42 VAT included. Shipping calculated for your destination.

Available to Order

Not sure which one? Ask us to confirm fitment first →
Delivery, customs and taxes Know the landed cost before you order

For UK customers, prices include VAT, customs and delivery unless checkout states otherwise. Outside the UK, shipping is shown at checkout and local customs and taxes remain your responsibility.

Lead times and urgent orders Check timing before you commit

Some products are made to order, imported or custom built. If timing matters, contact us before ordering and we will confirm the expected delivery timeframe.

Fitment checked before you order

Send the vehicle, engine and current setup if you want us to confirm the exact application before checkout.

Technical specifications
Specification Details
Brand ARB
Manufacturer part number RD157
SKU XADLRD157
Differential / axle Jeep JK Rubicon Dana 44, performance 35-spline upgrade
Vehicle application Wrangler JK Rubicon front or rear, with matching aftermarket 35-spline shafts
Axle shafts 35 spline
Gear ratio All supported ratios
Operation Selectable air-operated locking; open differential when disengaged
Supplied unit One Air Locker differential assembly
Carrier bearings Carrier bearings are selected separately for the installation.
Ring-gear outside diameter 216 mm
Ring-gear inside diameter 141.3 mm
Ring-gear mounting 10 bolts on 168.3 mm bolt circle
Required shaft upgrade Matching aftermarket 35-spline shafts
Air supply Compatible onboard air supply required; compressor purchased separately

Make your Rubicon's axle upgrade work for you

For a Wrangler JK Rubicon upgraded to 35-spline axle shafts, the RD157 provides selectable air-operated locking in the matching front or rear differential. It is a performance replacement for the specified factory locking-differential arrangement, letting you include stronger shafts and ARB locking in the same axle build.

SKU: XADLRD157

More grip on loose and uneven ground

On uneven ground, an open differential can let one wheel spin while the other has grip available. Engaging the Air Locker makes both wheels on that axle turn at the same speed, helping you tackle the section with controlled progress. Tyres and terrain still determine the grip available; the locker helps you use it.

The right axle for RD157

RD157 is the JK Rubicon-specific 35-spline design. Matching aftermarket 35-spline shafts must be used. A non-Rubicon Dana 44 uses different carriers. This listing is for one differential: upgrading both axles requires a separate correctly matched locker and shaft setup for each.

Normal driving when you switch it off

Disengaged, it operates as an open differential so the wheels can turn at different speeds in a corner. Engage it before a difficult low-traction section, with the wheels turning at the same speed. Switch it off when normal differential action is needed, particularly on firm surfaces or tight turns.

Choose your onboard air supply

The ARB CKMA12 single onboard compressor can operate one or two correctly installed Air Lockers. Add the ARB pump-up hose kit if you also want to inflate your tyres with it. The compressor and inflation kit are separate purchases.

If you regularly air down for trails, the ARB CKMTA12 twin onboard compressor offers more airflow for tyre inflation. Its Air Locker connection uses the separate 171503 manifold kit. Choose the twin for the extra inflation capability; the CKMA12 already has capacity for two lockers.

Professional fitting

A differential specialist sets the bearing preload, gear backlash and air sealing together, so your locker and existing gearset run correctly. Carrier bearings are selected separately for the installation. The air line is routed clear of heat and moving parts, then the locking operation is checked before the vehicle returns to use.

Delivery, customs and taxes

Know the landed cost before you order

For UK customers, prices include VAT, customs and delivery unless checkout states otherwise. For customers outside the UK, local customs and taxes remain your responsibility, and shipping is shown at checkout. If a shipping option is not available, email us and we will prepare a tailored quote.

Lead times and urgent orders

Check timing before you commit

Many of the products we sell are made to order, imported or custom built, so a lead time may apply. If you need a part urgently, contact us before ordering and we will confirm the expected delivery timeframe and process.

Questions before you order

Frequently asked questions

What will I notice off road?

When one wheel would otherwise spin, engaging the locker lets both wheels on that axle turn together. That helps the wheel with grip contribute to your progress on loose climbs, ruts and uneven tracks.

How does it behave on the road?

Switched off, it works as an open differential for normal cornering. Keep it disengaged on firm surfaces where the tyres cannot slip.

Which axle does RD157 fit?

Jeep JK Rubicon Dana 44, performance 35-spline upgrade with 35-spline shafts. Match the full axle and ring-gear specification above, including any bearing or shaft-retention requirements.

Do I need a twin compressor for two lockers?

No. The CKMA12 single onboard compressor can operate one or two correctly installed Air Lockers. The CKMTA12 twin is a useful upgrade if you also want more airflow for tyre inflation; use its separate 171503 manifold for locker connections.

What does this product supply?

One RD157 Air Locker differential assembly. The compressor is separate. Carrier bearings are selected separately for the installation.

Can I fit it without resetting the differential?

The installation includes bearing preload, gear backlash, air sealing and engagement checks. We recommend a differential specialist so the locker and your gearset are set up together.

Fitment first

Check fit before you order

Model year, engine, drivetrain, hardware and existing modifications can all change what fits. Check the applications and supplier notes above, or send us your exact vehicle and setup before ordering.

Check vehicle fitment
Need help with this product?

Send us your vehicle, year, current setup and any fitting date, event, trip or deadline before ordering. We will help check fitment, product choice and timing.

ARB RD157 Air Locker | JK Rubicon 35-Spline Upgrade
ARB RD157 Air Locker | JK Rubicon 35-Spline Upgrade
Available to Order £1,040.42