My new-to-me '65 truck was missing everything but the axles when I bought it, so basically I brought home a good body and frame. This "new" truck, a Dodge M37, is very similar to the classic civilian Power Wagons; it was equipped with a low-power, high-torque straight-six engine, manual transmission, a divorced transfer case, and unique dropout-style axles.
M37s were 3/4-ton truck used by the U.S. military from the early '50s to the late '60s. While five or six other guys at the office have the later iteration military 1 1/4-ton Jeep M715, I think the Dodge M37 is much better looking with big swooping fenders capable of clearing 40-plus-inch tires, and a narrower body perfect for four wheeling.
It was also time to get rid of my Red Sled, a '91 Chevy 3/4-ton, due to wiring and IFS headaches, so I figured the M37 would be a great home for all the old Sled's running gear and other old stuff I have lying around the shop. Since this would be the receptacle for discarded project bits and it's a faded green color and was full of trash when I bought it, the M37 was christened the Dumpster.
The classifieds ad said "army...
The classifieds ad said "army jeeps" for $500 each, so I called. The lady said there was a Dodge and some other stuff. A Dodge jeep didn't make sense, but she was selling stuff from an old renter who wouldn't pay his rent, and I had money burning a hole in my pocket. The next thing I know a '65 Dodge M37 was following me home.
I took the Dumpster to Pacific Fabrication and discussed the build with proprietor Kevin Stearns and his head tech, Jason Howerton. The plan was simple, to start with. I would swap the axles and powertrain from the Red Sled and add the Dodge 1-ton front axle I had brought home ages ago. But then I decided that the 4L80E automatic wasn't right for this old truck. This classic truck warranted a manual. As luck would have it, I had recently pulled the SM-465 from my Chevy Army truck.
Next was the big-block 454ci engine from the Sled. This throttle-body powerplant was still low in miles, but even when new it wasn't very impressive in power. In my conversations with the guys at Pacific Fab they recommended one of their late-model LS series GM engine packages. They sell both new and used LS V-8s with many different power numbers and simple standalone wiring harnesses. We decided on a used 6.0L small-block from a '04 GMC Denali (see "Awesome Engine in Any Truck," Sept. '09) that should offer around 300-325 hp versus the 230 from the 454.
With the engine mocked in place we moved forward with the front suspension and gear train. Doing an entire powertrain swap in a vehicle isn't a simple weekend project, but the goal is to see this truck running in Moab by Easter Safari. We'll be touching base with the Dumpster over the next few months and hopefully will be wheeling it by April Fool's Day 2010.
I'm imagining the Dumpster...
I'm imagining the Dumpster as a sleeper: ugly as sin at 20 yards but packed with cool parts just under its rough exterior, mostly used cool parts from old project trucks. It would be perfect for camping, wheeling, and cruising to the trail or ice cream stand. After removing all the old engine and front leaf suspension brackets I started mocking up the '04 GMC 6.0L V-8 with the crew at Pacific Fabrication. (See the complete story in Sept. '09.)
Steel bumpstop boxes will...
Steel bumpstop boxes will house Daystar foam bumpstops and land right on the AAM axle's bumpstop mounts. Sould the coils, shocks, and bumpstops fully compress, the axle pads will hit the steel bumpstop boxes before damage is done to the oil pan of the engine. At full metal-to-metal compression there is just 3/4 inch between the axle centersection and the oil pan.
I'm using a Dodge AAM 9.25...
I'm using a Dodge AAM 9.25 axle from a '07 Ram 3500 with all the factory mounts removed up front. I chose a front-link-and-coil, rear-leaf-spring suspension just like a new Dodge truck because of the ride quality and load-carrying ability but with our own link design. We put the axle at full compression centered under the frame and made sure it wouldn't hit the engine. Notice how the 6.0L oil pan has a convenient recess above the axle centersection. It is always best to build your suspension with the axle at full compression. This helps ensure against metal-to-metal damage under full-throttle romping.
The Dumpster's front suspension...
The Dumpster's front suspension will have three leading arm links and a Panhard (track) bar to locate the axle. Each link is 40 inches long and made of 2x1/4-inch-wall tubing. The 4140 steel links ends are from Evolution Machine and have massive 1 1/4-inch-diameter shanks. These greasable, rebuildable Heim joints have a 1 3/4-inch-diameter ball with a 3/4-inch bolt hole and an overall length of 6-plus inches. Evolution also supplied the jam nuts and the threaded bungs that will be TIG-welded into the link tubes.
We started with the leading...
We started with the leading arms mounting two lowers and the single upper arm on the passenger side with a separation of about 10 inches at the axle. The lower links are slightly lower than axletube to keep a good amount of separation without hindering ground clearance much, and the upper must clear the passenger-side motor mount at full compression. Also the lower link mounts will double as the shock mounts for the front axle.
On the frame side the Pacific...
On the frame side the Pacific Fab crew first drew up the link mounts with computer-aided design (CAD) while I ground and cleaned the rust and dirt off the frame. The frame mounts sandwich and box the frame while also using tubes through the frame for additional strength.
The CAD drawings were fed...
The CAD drawings were fed into a CNC plasma cutter, which then cut out the 1/4-inch plate. Though we used a computer, home fabricators could perform the same work with cardboard templates and a torch if need be. Next, the plates were cleaned and welded together on the framerails.
For the Panhard bar we went...
For the Panhard bar we went back to Dodge for a '09 heavy-duty bar off a new Dodge truck. This track bar is a heavy forged piece that curves around the front differential. I chose this piece because I assumed replacements would be available should I ever need one, and there are also many aftermarket adjustable versions.
The Panhard bar, axle, and...
The Panhard bar, axle, and frame mounts are designed to be in line with the steering draglink. I used a factory Dodge '09 and newer crosscar steering since it has a complete tie rod instead of the Haltenberger Y-link found on earlier Dodges. I had to extend the draglink to be the same length as the Panhard bar, but this should only improve the steering geometry. Next time we'll delve more into the steering and add some gearboxes behind the engine.