Quite proud of my daily-driver M880, although it gets severely abused in use. But, that's what old trucks are FOR!
Back about 2005, a local army truck restoration guy made the choice to unload ALL his M880 stuff. I got TWO complete trucks, and a big load of NOS parts, all for the princely sum of $900:
I immediately turned around and sold the worst one for $900 to an acquaintance to use as a farm truck.
Then, I was inspired to do a massive upgrade to the drivetrain. These trucks were built as cheaply as possible by Chrysler for the military - about 55,000 of them were sold, all with the weak-sister 318-2bbl, Dana 44F, Dana 60R, NP203 (chain-driven) full-time 4WD transfer case. They all came with manual steering. Just a crappy truck to drive.
My concept was to build "the truck that Dodge SHOULD have sold to the military". Cummins motor was 20:20 hindsight, and a no-brainer, since the first-gen factory Cummins trucks had identical frames as the M880, technically, a 5/4 ton truck. Should be bolt-in, right? Right! Here's the swap:
That was right after the engine was dropped in, back in 2007.
Also upgraded the trans to the 1993 47RH with lockup and overdrive. Dana 60 front and rear, 205 (gear-driven) part-time 4WD transfer case (see the lockout hubs!), 3.54:1 gears, Sure Grip front and rear. Power disk brakes on all 4 wheels. Power steering. Running the Chevy hydro-boost setup in tandem with the PS pump. Cuz, turbo-boosted motors don't have any vacuum to run the power brake booster! Tweaked the injector pump, 4" exhaust (no muffler).
Turned this truck into an absolute dream to drive. All the power you could ever want, 90MPH top speed, 18-20 MPG. With the upgraded front axle, GVW rating is 9800 lbs. It's been to Florida twice, and to Arizona 4 times.
Still wearing its 1980s NATO camo scheme. It's due for (another) repaint, and I'm going to put it back to the 1970s 4-color camo scheme.
M880s don't garner much respect in the military vehicle collecting world. Won't be long and they'll all be gone... A shame, because they're so highly serviceable. I'll drive mine until they take my license away!
I had a bearing failure about a year ago and WASTED the rear axle housing. The heat actually melted the left axle shaft in two! I knew of a potential donor truck in a nearby junkyard I found back in the mid-1980s. 1967 Dodge D250. Still laying there. Bought the rear for $100, swapped the gears, and bolted it right in. Gotta love Dodge interchangeability! Great thing was that the factory pinion depth setting was exactly the same in both the wrecked axle and the donor axle. So, my 3.54 Sure Grip gears dropped right into the 'new' housing. I was back on the road in two days.