Dana 44 Axleshaft - LOCK and LOAD

We win here or lose everywhere. If we win here, we improve our chances of winning everywhere." General Douglas MacArthur said that. Since he's practically as American as any one person can be, we thought it appropriate to start with in another segment of our Project All-American buildup.

Besides, if you get down to, it applies rather well to the building of the ultimate 4x4. How, you may ask? If you're going to do something, you have to do it right. You don't build a vehicle with an Achilles' heel after sparing no expense in every other aspect of it. Win in everything or lose everywhere. That's what Big Mac meant. And that's what we've set out to accomplish with Project All-American.

Since we'd selected a pretty hefty tire and wheel combination (37-inch Goodyear MT/Rs on 15x10-inch MRT steel bead locks), axle strength became of great importance. After all, you can't be snapping 'shafts or slipping tires while in combat, er, we mean, on the trail. For this matter, we opted to use one of the most common and reliable front-axle applications around, the venerable Dana 44. And when it came time to find a builder, we didn't have to look any further than the far south of California, where we discovered Mechanically Inclined Techs (M.I.T.) Drivetrain Specialists in El Cajon.

The crew at M.I.T. isn't just one of the most experienced around, they're also some of the wackiest and good-natured folks in the industry. They even didn't mind (so much) when we showed up an hour late only to discover we'd ordered the incorrect Yukon Gear & Axle gearset from Randy's Ring & Pinion and essentially blew a whole day of their calendar. Thankfully, Randy's Ring & Pinion remedied the situation by shipping the correct set faster than we thought possible, and we were back on track in no time.

Another end in the strength factor of our axles lay within our choice of axleshafts. Wanting the meatiest setup possible, we discovered Moser Engineering and its M/E Dana 44 Custom Alloy Front Axleshafts. The Moser units are redesigned and beefed up in critical weak areas around the U-joint and constructed of the same material that it uses for its racing applications.

We topped these with spindles, U-joints, and a pinion yoke from Spicer. Lastly, we desired a traction-aiding device that would allow us the same level of on-road control that it would offer in off-road capability. ARB reared its head with its innovative Air Locker and we were sold. Check out the sidebar about its functions for the low-down.

So here it begins, the mechanics of Project All-American. You can look forward to the buildup of the rear Tera 60R next month, and leaf spring and frame tech will be soon to follow. And, hopefully, with each stage, we'll continue to "improve our chances of winning everywhere." Stars and Stripes forever, people. Don't forget it.

The Workings of It:
The ARB Air Locker

Appropriate to its name, the ARB Air Locker is just that. It's a locking differential that is capable of being locked using pressurized air. What's the benefit of this? For one thing, it gives you the option of a conventional or fully locked differential at the push of a button. This means you can roll down the highway at speed and make turns without the typical locker bump, or traverse the most difficult of trails without losing grip. Since it's capable of being manually engaged and disengaged, the ARB is an excellent choice for front diff applications because it has no effect on the steering when disengaged.

When the unit is activated via an in-cab button, an air solenoid valve located on the compressor opens, allowing air to be fed down a nylon tube to a bulkhead fitting on the differential housing. Another tube runs from there into the diff case to an air-seal housing installed on the bearing journal of the ARB unit, where a small air inlet hole in the bearing journal enables air to be sent into the locker while it's rotating.

This compressed air, in turn, activates an annular piston inside the locker, which locks the axleshafts together with a large locking gear. Once the in-cab switch is shut off, the compressed air is spent out of the solenoid valve, and built-in coil springs within the Air Locker return the locking gear to the disengaged position. It's technology at its best, people.