Classic Machines TractorsClassic Machines: The Allis-Chalmers HD-16 tractorContrafed PUblishingMarch 30, 2016September 4, 2021 by Contrafed PUblishingMarch 30, 2016September 4, 2021 Replacing the previous model HD-15 in the Allis-Chalmers line of track type tractors the HD-16 was introduced with much fanfare in 1955. By Richard Campbell...