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 ...

Forty years ago this September, Caterpillar rolled off of its production lines 10 pilot models of the world’s largest, most powerful dozer, destined to leave a lasting legacy on the industry. The Cat ...