ContractorThe Allis-Chalmers HD-15Contrafed PUblishingSeptember 7, 2022November 28, 2024 by Contrafed PUblishingSeptember 7, 2022November 28, 2024 One of the last GM-powered track type tractors offered by Allis-Chalmers, the HD-15 was also a top performer and paved the way for the subsequent...