Ford 9 3/4-Inch ARB Air Locker

After you remove the differential cover and drain the gear oil, check the gear pattern to determine the current gear mesh. With the axleshafts out, remove the factory carrier.

After you remove the differential cover and drain the gear oil, check the gear pattern to

Until recently the only locking differential option for the Ford 93/4-inch axle was to buy an '09-or-later Ford F-150 pickup with the factory electronic locking diff. With nearly six million 93/4 axles on the street (commonly found in the F-150 and Expedition), it's a wonder that nobody has offered a selectable locking differential until now. ARB, the world leader in air locking differentials, saw the potential of the 93/4 axle and introduced the RD150 Air Locker for the Ford 93/4 34-spline axle.

As we write this, the ARB RD150 93/4 Air Locker is only available for use with the factory gear ratio, but by the time you read this it should be available for all aftermarket gearsets and ratios. Since our '08 Ford F-150 was in need of a better traction, we went to 4Wheel Parts in Redondo Beach, California, for the install.

Applications
The Ford 93/4 ARB is available for these '97-current Ford vehicles.
•F-150
•Expedition
•E-50, E-250, E-350 vans
•Lincoln Navigator

Arb Locking Differential Differential Spreader

Tools Of The Trade
Installing an ARB Air Locker (or any locker, for that matter) into an axlehousing can be daunting for professionals and amateurs alike. In addition the tools to perform this work are either difficult to get or just plain expensive. For this reason ARB has introduced a line of air locker service tools, including an easy-to-use differential spreader (shown), a clamshell-style bearing puller kit, an air locker test gauge, a contoured shim driver tool set, and adjuster nut pliers for setting preload on adjuster-nut-type differentials. If you do any kind of differential work these tools from ARB are must-haves.

Since we are reusing the stock ring-and-pinion, we carefully removed the ring gear and tone ring from the factory carrier. This will be installed on the ARB when it is put in the housing.
Since we are reusing the stock ring-and-pinion, we carefully removed the ring gear and ton
The ARB differential (left) is manufactured from heavy cross-sectioned nodular iron castings. This should make it extremely robust, and comparing it alongside the factory unit we completely believe it.
The ARB differential (left) is manufactured from heavy cross-sectioned nodular iron castin
Before the new differential can be installed it is necessary to drill and tap the axlehousing in order to screw in the air supply line bulkhead. Be sure to select a location that will not interfere with the internal workings of the axle, such as the carrier bearings or ring gear.
Before the new differential can be installed it is necessary to drill and tap the axlehous

Prior to installing the ARB, you need to press into it the ring gear, tone ring, and bearings. Then place the unit inside the axlehousing and bolt the carrier bearing caps into place, securing the ARB in the housing.
Prior to installing the ARB, you need to press into it the ring gear, tone ring, and beari
Even though we only changed the carrier it is still a good idea to make sure the differential is set with the proper gear backlash. The skilled techs at 4Wheel Parts were able to get a great contact pattern with very little shimming.
Even though we only changed the carrier it is still a good idea to make sure the different
One of the most important steps of any ARB install is routing the copper air supply line. This line must stay out of the way of the ring gear and be free of kinks and cracks for smooth, long-term operation.
One of the most important steps of any ARB install is routing the copper air supply line.

Air is the life's blood of the ARB, so it is important to route the compressor air line away from sharp edges and hot exhaust and to ensure that it's free of bends and kinks. If this line becomes compromised you will be left with an open differential when you need the locker most, exactly what we are trying to avoid.
Air is the life's blood of the ARB, so it is important to route the compressor air line aw
Quality oil is critical to a differential's long life. We went with Amsoil Severe Gear 75-140 to help protect our new ARB from the abuse it will surely see.
Quality oil is critical to a differential's long life. We went with Amsoil Severe Gear 75-
Special thanks go to 4Wheel Parts in Redondo Beach. The crew performed a quality installation and got us on the road to test out our new locker quickly and professionally.
Special thanks go to 4Wheel Parts in Redondo Beach. The crew performed a quality installat

SOURCES
4Wheel Parts 400 W. Artesia Boulevard Compton CA 90220 877-474-4821 www.4wheelparts.com	AMSOIL 925 Tower Ave. Superior WI 54880 800-777-8491 www.amsoil.com
ARB 4x4 Products 720 SW 34th Street Renton WA 98057 800-761-8192 http://www.arbusa.com