Allis-Chalmers D-17 Tractor and All-Crop 72 Combine August 31, 2013 by farmlifetoday bigtractorpowerSat, August 31, 2013 4:56pmURL:Embed:Allis-Chalmers D-17 Tractor and All-Crop 72 Combine harvesting soybeans at the 2013 Half Century of Progress Show