Allis Chalmers Other models

The register lists here 5 versions with 40 to 152 kW, or 53 to 204 hp, with Allis-Chalmers engines and a GM Detroit Diesel 6-71 in the HD-21.

Such crawler dozers and backhoe loaders were used in earthmoving, road building and civil engineering, where the HD range, alongside makers such as Caterpillar and International Harvester, was a fixture of the post-war and 1960s US market.

Track undercarriages such as the HD range's spread the machine's weight over a large footprint, giving low ground pressure and good stability on loose or uneven ground, but they must be moved by low-bed trailer on the road. The wheeled D17 backhoe, by contrast, can drive itself on the road but loses traction and stability on soft ground.

Buying used, on these vintage construction machines the condition of tracks and rollers, clutch and final drive matter most, and on the HD-21 also the Detroit Diesel engine with its characteristic two-stroke technology; parts run through dealers specialising in classic construction machinery.