How Mitsubishi Diesels Got Into pre-1978 Dodge D100 trucks
The players:
- Industrial Irrigation Engines started assembly of Chrysler industrial engines for irrigation in 1955, using them until 1995; they also used Mitsubishi diesels. Today they use engines from John Deere, Yanmar, and General Motors.
- Pettit Automotive, local repair garage and tinker, used to work for Industrial Irrigation, before he retired and opened his own repair shop to keep him self busy and away from honey do’s.
- (SBI) Spitz & Blauvelt Inc, a local aluminum foundry and the area’s largest job machine shop with welding and repair; the company moved five miles west to Juniata, Nebraska in 1984 and became Phoenix Casting.
The Plot:
Industrial Irrigation’s sales force got the bright idea that, to help promote their newly acquired Mitsubishi diesel line, they would convert some of there service trucks over to diesel and maybe even offer it as a conversion kit they could do for the farmers.
John C. (Jack) Osborne, Industrial Irrigation’s president (and the younger brother of retired past Nebraska Cornhusker coach Tom), talked the idea over with Mr. Pettit and both felt this could be done, so a diesel engine and Dodge D100 truck were taken down to Pettit where he started by pulling the gas and figuring what he needed to make to connect them back together. The D100 had a 360 and A727 automatic in it; later ones were done with manual transmissions.
Mr Peditt came over to our shop, SBI, for help with the aluminum casting he needed for the adapter; we were two blocks south of his shop. We helped him design the adapter, made the wood pattern, cast the parts, machined them, and also made a steel part that went from the flywheel to the Chrysler flex plate.
We had just finished our first adapter to put a John Deere 4219 in a ¾ ton Chevy that was a service truck for the John Deere dealer, Valley Engines in Wayne Nebraska; we figured this may have been where Industrial Irrigation got the idea!. We also did one for their 1 ton GMC to a JD 4239T; these engines are a bit heavy, at 950 lbs. for a 239 cubic inch diesel, but they do last forever.
The Mitsubishi showed it had one basic problem up front as soon as it was in the truck and running: the RPM was limited to 2400, which made for a great go-for in town but top end was 48 mph. They dropped the rear gear from 3.56 to 3.07, and found the power curve now needed a turbo to help go over 45 mph
They also had the local injector wizards, the Fobin Brothers, working on the injector pumps to speed up the diesel. I seem to remember Zigy game up with a different injector pump that would run it up to 3500 rpm, but the conversion cost on that was more than the cost of the diesel! The John Deeres on the other hand could easily be cranked up to 3600 rpm (the valves float around 4200). Both of these trucks were still being used a few years back when I went through Wayne and stopped by to check on them.
The Deere version was the forefathers of the adapter we make to day to convert SAE engine over to use Chrysler, GM or Ford automotive style transmissions. You would be surprised at some of the requests we get today for adapters that people think should be in stock. As for the Dodge diesel adapter, we did four to six castings, and this adapter faded away.
Some of our stock ring casting in the machine shop waiting for machining. Having your own aluminum foundry has its advantages when it comes to making adapters.
Our HL-6 has a 18” chuck with a 32” swing and does all of our production runs on the rings. Specials are still made in one of our large engine lathes.
Postscript (from the Allpar staff)
When the fuel crisis hit, Dodge was not prepared, but perhaps someone heard of Industrial Irrigation’s work. In 1978 and reportedly beyond, Dodge sold, as a factory option, the same Mitsubishi engines in D150s, D250s, and Power Wagons; the engine, the Mitsubishi 6DR5, was a straight six sized at 3950 cc, with 105 hp at 3500 rpm, and reportedly virtually identical to the Land Cruiser diesel engine. It came without a turbocharger, providing good mileage (reportedly over 20 mpg) but limiting top speeds; the turbocharger was added by many buyers afterwards. These engines do not appear to be listed in the Standard Catalog of American Light-Duty Trucks.
