ARB Air Locker Dana 44: Fitment, Install Basics and Setup Tips

Updated November 2026

The ARB air locker for the Dana 44 is a pneumatically actuated rear or front differential locker that forces both axle shafts to turn at the same speed when you need traction. This guide walks through what to confirm before buying, how the install and air system come together, how to set the locker up so it engages cleanly, and where owners most often run into trouble. By the end, you should know whether your Dana 44 is a good candidate and what the job involves.

What the ARB Air Locker Does on a Dana 44

An air locker replaces the open or limited-slip action of a standard carrier with a positive lock. When you trigger it, an air-actuated piston moves a sliding collar that engages the side gear, so both wheels on that axle spin together. The Dana 44 is a common platform for this upgrade on Jeep JK and TJ builds, as well as various Ford and Dodge applications, because the axle is strong enough to handle the added torque loading on the trail.

Shopping for one? See our guide: ARB Dana 60 Air Locker Review (2026): Features and Performance.

The trade-off is that a locked axle does not steer well on pavement. Most owners run the locker open on the street and lock it only when the trail demands it. If you want a broader overview of the design before you commit, see What Is an ARB Air Locker? How It Works and When to Use One.

Confirm Fitment Before You Order

Dana 44 covers several housings, pinion sizes and ring gear setups, so fitment is the first thing to nail down. Check these items against the locker kit listing and your axle tag:

• Axle tag and housing type: Find the axle code stamped on the tag, usually on the driver-side cover or the housing near the ring gear. Confirm the housing width and axle flange style match the kit.
• Ring gear and gear ratio: The locker is typically sold for a specific gear ratio. Confirm your ring and pinion ratio, as a mismatch can mean the locker will not fit or the gear set will not be supported.
• Axle shaft spline count: Dana 44 axles come in different spline counts. Verify your shafts, since a locker kit assumes a particular set.
• Cover and bolt pattern: Confirm the cover gasket and bolt pattern on your carrier.
• Front or rear application: Make sure the kit is designed for the axle position you are upgrading.

If anything is unclear, match the axle code exactly and check with the manufacturer or a reputable parts dealer before buying. Ordering the wrong carrier configuration is the most expensive mistake you can make at this stage.

Tools and Parts You Will Need

Plan the job before you start so you are not stopped partway through. A typical Dana 44 locker install requires:

• Socket set and torque wrench with metric and standard sizes
• Gear oil (check the manufacturer spec, usually a 75W-90 or 75W-140 synthetic gear lube)
• Gasket sealant and a new cover gasket
• Pinion crush sleeve or collapsible spacer, if the procedure calls for one
• Dial indicator or magnetic base for backlash and pinion depth checks
• Bearing puller and installer tools, or access to a shop that has them
• Air line, fittings, solenoid and compressor if the kit does not include them

Check your kit’s instructions for exact torque values and the gear oil quantity. Specs vary by kit and carrier, so use the numbers from the instructions and not from memory.

Step-by-Step Install Overview

A full install is a serious job that involves removing the axle, opening the carrier and setting gear mesh. The outline below gives you the sequence; always follow your kit’s instructions for specifics.

1. Drain and remove the axle. Lift the vehicle securely on stands, drain the gear oil, disconnect the brake lines and remove the axle shafts.
2. Remove the carrier. Unbolt the carrier from the housing and set it on a clean bench.
3. Disassemble the carrier. Remove the bearing caps, the ring gear and the differential case. Note the orientation of every part.
4. Install the air locker assembly. Fit the locker body, piston, collar and springs into the case as the kit directs. Confirm free movement of the collar before going further.
5. Set bearing preload and pinion depth. This is the step that determines gear life. Use shims and a dial indicator to set pinion depth and then the ring-and-pinion backlash, typically to the range the manufacturer lists.
6. Check gear contact pattern. Apply marking compound to the ring gear teeth, rotate the assembly and confirm the pattern is centered and correct.
7. Reassemble and reinstall. Torque the carrier bolts, install the cover with fresh gasket, fill with the specified gear oil and reinstall the axle shafts.
8. Route the air system. Mount the solenoid and compressor, run air line with clean fittings, and protect lines from heat and rock damage.

Pinion Depth and Backlash Checks

Pinion depth and backlash are where many home installs go wrong. Set pinion depth first using the shim pack and your kit’s reference value. Then set backlash by adjusting the bearing caps, keeping the total preload within spec. Measure at several points around the ring gear, since variation can point to a runout or seating issue.

Air System Setup

Most ARB systems run from a compressor and a solenoid valve that you control from the cab. Mount the compressor where it stays dry and away from heat, and use a sturdy switch with a fuse. Use the air line size the kit specifies and keep runs short where you can. Leaks at the fittings are common, so check every connection with soapy water before you call the install finished.

Setup, Testing and Use on the Trail

Once the carrier is back in and the air system is running, test the locker on the ground before trusting it on a trail. Raise the axle or chock the wheels, then engage the locker and confirm that both wheels turn together. Disengage it and confirm the axle returns to open. Check that the compressor builds pressure to the level the kit specifies and holds it when the vehicle is idle.

On the trail, engage the locker before you need it, not after a wheel has already spun. Air lockers respond best when the vehicle is moving slowly and the wheels are not fully slipping. Disengage on pavement to keep steering predictable. If the locker does not engage, troubleshoot the air supply before you suspect the mechanical parts. For a set of common causes and fixes, see Why Is My ARB Air Locker Not Engaging? Causes and Fixes.

Common Mistakes

• Skipping the contact pattern check. A quiet, centered pattern protects the gears. A loud or lopsided one will wear the ring and pinion quickly.
• Reusing old gaskets or crush sleeves. Replace them when the procedure calls for it, since leaks and preload errors start here.
• Using the wrong gear oil. Lockers and limited-slip-style actions are sensitive to fluid. Use the spec in your instructions.
• Running air lines near the exhaust or sharp edges. Heat and abrasion cause most air system failures.
• Locking the axle at speed. Engage at low speed and keep steering inputs gentle while locked.
• Leaving the locker engaged on pavement. This makes the vehicle hard to steer and can stress drivetrain parts.

Tips for a Cleaner Install

• Photograph the carrier and shim locations before you disassemble anything.
• Label bolts and brackets by location so reassembly goes smoothly.
• Clean all mating surfaces thoroughly before applying sealant.
• Break in the new gear set gently for the first few hundred miles, avoiding hard lock-to-lock loads.
• Check the carrier bolts and gear oil level after the first few drives.

Recommended gear

• Synthetic gear oil matching the kit spec: Use the viscosity your instructions call for, since the locker’s sliding parts and gear set depend on it. View on Amazon
• Dial indicator with magnetic base: Needed for accurate pinion depth and backlash checks during a proper setup. View on Amazon
• Gasket sealant for differential covers: Helps prevent leaks at the cover and fittings during reassembly. View on Amazon
• Gear marking compound: Used to check the ring and pinion contact pattern before final assembly. View on Amazon

FAQ

Can I install an ARB air locker on a Dana 44 myself?

It is possible for a mechanic with carrier experience and the right measuring tools. Pinion depth and backlash setup are the hard parts. If you are not confident, have a shop handle the gear setup.

What gear oil does a Dana 44 air locker need?

Use the viscosity and quantity listed in your kit instructions. Many setups use a synthetic gear lube in the 75W-90 or 75W-140 range, but the spec for your build governs.

Does an air locker work on the front Dana 44?

Some kits are made for front and rear applications. Confirm the part is designed for the front axle before ordering, since the two carriers differ.

Why does the locker make a clicking noise?

Some clicking during engagement is normal as the collar moves. Constant clicking or grinding while driving can point to a setup or wear issue, and you should inspect the gear set.

How much air pressure does the system need?

Your kit specifies the operating pressure. Run the compressor to that level and confirm it holds when the vehicle is idle.

Can I drive with the locker engaged on the highway?

No. A locked axle makes steering difficult and stresses the drivetrain at speed. Disengage the locker before returning to pavement.

Should I compare this locker with other options before buying?

Yes. Compare fitment, air system requirements and warranty. For a related comparison, see Dana 44 Air Locker Review (2026): Pros, Cons and Who It Is For and Ox Locker vs ARB Air Locker: Which Should You Choose?.

Is professional installation worth it?

For many owners, yes. Gear setup errors can destroy a ring and pinion quickly, so a shop experienced with Dana 44 carriers can be worth the cost. Consult a qualified professional if you are unsure about any step.

Conclusion

An ARB air locker on a Dana 44 gives you a reliable positive lock when the trail calls for it. Confirm fitment against your axle tag, follow the kit’s gear setup closely, and build a clean air system. Test the locker on the ground before you rely on it, and disengage it on pavement. Done carefully, this upgrade can be a long-term part of a capable trail rig.

Related reading

• Installing ARB Air Locker Dana 30: A Step-by-Step Guide for Beginners

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