Inside the Military M35A2 (aka The Deuce-and-a-Half)Posted in Project Vehicles on August 1, 2011
When it comes to big Jeeps, few are larger than the M35A2. While the giant 21⁄2-ton military 6x6 may not resemble the modern-day Wrangler, it was a product of the Kaiser-Jeep Corporation. Built by both Kaiser-Jeep and AM General in the ’60s and ’70s, the now classic Deuce-and-a-half trucks are among some of the cheapest and largest off-road vehicles you can buy. And while mud runners and hardcore wheelers have pillaged their 21⁄2-ton Rockwell axles for decades, there is more to the giant trucks than beefy running gear.
Weighing in at 13,000 pounds, the Deuce is no lightweight, but most states do not require any special license or endorsements to drive one. Throughout its long production run, a variety of cargo, box, utility, and troop carrier versions was produced. The most common Deuce is the troop carrier. In the ’80s many of the Deuces received a revamp along with a host of new parts such as double beadlocks, Caterpillar engines, and air-assist steering. The later-model Deuces are far better than the early ones, but are also much pricier and harder to come by.
Luckily, a late ’60s and early ’70s turbodiesel truck that hasn’t received the high-priced revamp can be picked up for around $2,500 and up from government and private auctions, military surplus stores, and country fields across the nation.
Since owning one of these 6x6 Goliaths is easier than ever, we’ve compiled some items to look for when browsing for your new-to-you Deuce.
If you live in the Southeast it’s a safe bet that you’ll find rust scattered around the Deuce. Buying a used 21⁄2-ton truck is similar to purchasing a used car. Always check to make sure that the gauges are working, the tires are in good shape, and that the vehicle can move under its own power. Just remember, towing a 13,000-pound truck home isn’t the easiest option.
Creature comforts are at a minimum in the Deuce, as the seats are lightly padded, heat was often optional, and A/C comes by way of a removable soft top (if equipped) and windows that roll down. These trucks also have no insulation, so they are comfy in cold climates but can be warm in the summertime. If your truck doesn’t have a suspension seat or parts are missing from it, don’t fret. Seat upgrades and parts are easy to come by from places like Red River Parts & Equipment (www.redriverparts.com).
The 37-inch factory tires and 20-inch wheels are pretty heavy and contribute to the Deuce’s low top speed. Upgrading to a 44-inch Military tire will help offset the low 6.72 differential gearing and overall top speed of the truck. Another great source for complete trucks as well as Deuce parts is Boyce Equipment (www.boyvceequipment.com).
Virtually all Deuce-and-a-halfs are fitted with massive inline-six multifuel engines, which make them great for burning old engine oil and diesel fuel mix. Though the giant inline engines are all pretty stout, the one to look for is the turbocharged version, commonly referred to as the “whistler” engine. Top speed on these trucks is around 45 mph with factory tires, so don’t expect to win any drag races.
Be sure to listen and check the air compressor and air tanks (located under the bed) when you fire up the truck. Air is a huge part of these trucks. Air powers the wipers, assists the brakes, and aids the steering on some later-model trucks.
One common area of wear is usually found at the pinion bearings. A good way to check for this is to put the truck in Neutral and have a buddy sit inside with his foot on the brake while you attempt to twist the drivelines by hand. You are looking for excessive slop. Greasy U-joints and leaky axle seals are very common and usually not a cause for concern.
The M35A2 uses two 12V batteries to power its 24V electrical system. It’s pretty common for the battery box (located under the passenger door) to be found in rough and rusty condition. For cleanliness and reliability we’re big fans of converting over to dry-cell batteries such as Optima’s (www.optimabatteries.com) and Odyssey’s (www.odysseybatteries.com).
Besides having an odd shift pattern, the Spicer 3053A five-speed transmission is virtually indestructible. Mounted behind the five-speed is either an ultrastrong Timken T136-27 air-shift transfer case or the less desirable Timken T136-21 sprag-style case. A sprag is a form of clutch that only engages in one direction. As the rear “slips,” the sprag automatically engages the front end. Though there are aftermarket kits to convert the sprag unit to air shift, it’s easier to find a truck already equipped with the air-shift case. Remember, buying a Deuce the way you want it is much cheaper (generally) and less time-consuming than trying to piece it together after the fact.