Almost have the working prototype for a selectable air locker for folks without the factory rear TOD rear locker. Final product will be a Billet case half to replace the factory differential case half and an ARB carrier unit. This will give the ability to manually lock the rear differential independent of the terrain response system settings or in case of failsafe operation. The ARB differential is also much stronger than a stock differential. The ARB has 4 spider gears vs stock with 2 spider gears with a single pin. Billet housing will include a larger carrier bearing and reinforced bearing race support. Case half will have all provisions to connect air line without the need to drill and tap.

 

@sarek - A giant amongst men... Well done!

 

He used my old open diff I sold him at 80% off. I deserve sone credit...plus he got all of my east cost customers....Mark

 

 

Is that for the 2020 or the 2021 and newer? Do you have instructions anywhere so that I can see wat is involved?

Last question. Given this is stronger than the original differential, if you were in the market for a used Defender, would you rather find one that has the factory electronic locking differential, or one without and add the ARB?

 

I would not want the factory active diff especially in a used vehicle. I would run the factory open diff which i ran for 2 years with no issues of capability and add the ARB if i felt i needed it or to have peace of mind

Basically you drain and remove the differential. Then take all the case half bolts out of it. Split it in half and lift out the carrier/bearings/ring gear assembly. Unbolt the ring gear from the stock carrier and bolt onto the ARB. I always loctite those bolts after i clean all the threaded holes in the ring gear. Also, press the included new bearings onto the ARB carrier.Now, replace the bearing race in the larger diff case half (the one u lifted the carrier out of) with the new one provided. There is a factory shim under it. Leave it in. No additional shims are typically required on that right side carrier bearing. This adjusts backlash, which should not change. Then drop the ARB into the right case half. The left /smaller case half, the seal and the drain/fill plugs get removed and installed on the new Sarek case half that is part of the kit. Also the new larger bearing race gets installed in that that one with a set of suggested shims behind it including the ARB seal housing. This shim stack is the one that carrier bearing preload. This one is tedious and very important. Basically you keep bolting the case half on and off, adding or removing shims until the setting is correct. New bearings have more preload than used since they "break in". Once this is done, the sealant is applied to the case half flange and it is bolted together. At this point the the ARB is leak/function bench tested. After that is done, it is installed and filled with fluid. You run the air line to where your compressor is mounted. Then install the provided solenoid and switch to your ARB compressor.

As you can see, the removal and installation of the Differential assembly is pretty straightforward. We do suggest a qualified shop does this, but a diy could do it especially with a lift. As far as the disassembly of the differential, installation of the locker kit and air testing, this would be better suited for a shop or person that has the special tools and knowhow in setting up differentials. For someone like that, it will be very straightforward and provide peace of mind. We will also build a diff for you if u if u send it to us or bring us the vehicle.

 

This is currently for the 2020. As u can see on the photo, the pinion has a flange and not a splined shaft with a big collar nut. That differential, in 20201, they decided to weld the ring gear to the carrier, so similar to the BMW diffs, the ring gear needs to be machined off and drill/tapped. Once that is done, the assembly is the same. We are building the prototype currently and will be tesring soon. Then we will offer this option either by core exchange differential or with you shipping us just the carrier/ring gear and we send back the arb with your ring gear attached along with the rest of the kit.

We are also doing gear ratio changes for the folks running 35 inch or larger tires. That would also be a core exchange deal where we send the differentials ready to install and you send back the cores.

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Extremely helpful. Thanks.