With a weight of 70 tons and boasting 524 horsepower, the HD-41 crawler tractor made headlines as the largest built up to that time. Allis-Chalmers gave at-tendees a taste of things to come at the ...

Lots of guys can give you the make, model and year of a vintage car – but Chuck Logan could do that for tractors and excavating equipment. Just on sight, he knew a 1972 Allis-Chalmers HD-41 dozer from ...