The Overland Train Mark 2 performance standards were proposed in 1958 to R. G. LeTourneau, Inc. Engineers had to work backwards to determine how to best meet the Army’s needs for self support, cargo capacity, and resiliency. In total, the Mark 2 was able to carry 7,794 gallons of fuel. The control car, power generating car number 1 and 2 all had space heaters with 150 gallon tanks, adding on an additional 450 gallons of fuel.

Mark 2 fuel capacity. Image: snippet from Phase 4 Design Report

Aerial view of the Mark 2 during testing at R. G. LeTourneau, Inc. Image: Lloyd and Larry Smith.