Allis-Chalmers attracted a large and faithful following in the small tractor market with the Model B, C, and CA.
These three models spanned a 20-year period from 1938, when the Model B was introduced, to 1958, when production of the CA ended.
Introduced in 1959 were the Allis-Chalmers Models D-10 and D-12. Both were attractively styled and are popular now with Allis-Chalmers collectors for restoration.
It is estimated that about 9,000 to 10,000 units were built of the Model D-10 and about the same number for the Model D-12.
The D-10 and D-12 were nearly identical, with the major difference being rear wheel width. The D-10 was designed for straddling one-row crops. The D-12 had a wide tread for two-row crop work. The rear wheels were power and adjustable.
A close look at the D-10 and D-12 would show evidence that the good features of the Allis-Chalmers B, C. and CA were incorporated into the engineering design of the D-10 and D-12. New features included increased horsepower, a fourth gear with a speed of 11.4 miles an hour, snap-coupling design for mounted implements, live PTO, traction booster, and power steering.
The D-10 and D-12 had attractive styling with new grille and hood design. Both models were powered by a 138 CID engine compared to the 125 CID engine in the Model B. The D-10 and D-12 engine operated at 1650 RPM to produce about 20 horsepower on the drawbar.
Fuel economy was about 10.7 horsepower hours per gallon of gasoline.
The D models were available with only gasoline engines. The D-10 originally sold for about $1,900. The D-12 was available for about $2,800. But the end of the production run, both models sold for from $600 to $800 more. The price reflected an improved engine with about 24 horsepower.
The D series included a model D-14 that was built for only two years, 1957 through 1959. It somewhat resembled the WD-45 and was the forerunner of the entire D series.
The D-14 was offered with gasoline or propane fuel, also as Orchard, Industrial, Row Crop or wide-front design.
By the end of 1969, Allis-Chalmers ended production of all D series, including the D-10, D-12, 14, 15, 17, 19 and 21. Most popular of all of these was the D-17.
Editor's note: Written by Delmer Dooley, an agricultural engineer, former high school ag teacher (Platte), expert on vintage tractors and farmer. The author lives with his wife on his parents' homestead farm near Ramona in Lake County.