The LeTourneau TC-497 Overland Train Mark II was the culmination of several years of multi-wheel trial and error. Starting with the idea of a diesel-electric transmission that drove multi-wheeled vehicles, the end result was a vehicle that sent electricity to every wheel – a massive vehicle. The earliest overland vehicle LeTourneau built was the VC-12 Tournatrain, which, like a locomotive, had a power truck with a 500 horsepower Cummins VT-12 diesel engine, and three 20-ton trailers. The engine powered every wheel and, connected to each other with a flexible towing arm, it was capable of long distance overland travel while hauling heavy loads.

Testing began in 1953 and, by 1954, the VC-12 Tournatrain added four trailers and an additional engine in a trailer at the rear. It could tow up to 140-tons over difficult terrain and in inclimate weather. Its ability to haul heavy loads over land that had no roads was unparalleled at the time.

Other commercial vehicles followed in the VC-12 Tournatrain footprints, but it was the United States government that ordered the largest and most powerful version – the LeTourneau TC-497 Overland Train Mark II. This massive Overland Train had four 1,170-hp Solar 10MC turbine engines. Each wheel was powered electrically and maximum speed was about 20 mph under full load.

The massive cab supported a crew of (up to) six along with a galley, bathroom and sleeping quarters. The main car was over 30-feet tall. At it final, maximum length, the LeTourneau TC-497 Overland Train Mark II measured over 570-feet long. If needed, they could add additional trailers. Range was between 300 and 400 miles under load.

The LeTourneau TC-497 Overland Train Mark II had several advantages over its predecessors including the ability for each trailer to power-steer itself. Rather than suffer from the arc of a turn reducing itself, each trailer would turn when signaled. This allowed the LeTourneau TC-497 Overland Train Mark II to negotiate fairly tight turns.

Completed in 1961 (after extensive testing in the desert and snow), the LeTourneau TC-497 Overland Train Mark II was ready. While it performed well, it was retired before it could reach its potential. Heavy-lift helicopters were perfected and it rendered the massive vehicle obsolete.

Sadly, there are no working versions of any of the LeTourneau overland trains out there. Some are rusting in Alaska while a LeTourneau LCC-1 Sno-Train is on display at the Yukon Transportation Museum in Whitehorse, Alaska. We supplied a few old films for you to get an idea of how fantastic these vehicles were.

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