Smallest Capacity ?
The LeTourneau Model D4 with model Q Carryall is the smallest capacity scraper made by LeTourneau. 2.3 cubic yard . This is a Self-Propelled unit with a 45 hp Continental Gas engine.
The Tractor Towed models D,and X are 3.5 cy, and the Model Z is 2.6 cy.
The following pictures are of my collection. Model X scraper and Model Q.The Model D4 Tournapull tires are loaded with calcium chloride. Makes for a heavy machine to move. There is no bar, to lock the tractor rigid for shipping (straight line movement), like the current Cat loader and graders. With a dead engine it flops from side to side. Makes for difficulty in loading.
The following data are from a 1959 CPH, and a book by Keith Haddock "Giant Earthmovers"