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#7 Caterpillar 20 Experiment


Roster #T048 Caterpillar Model Experimental 20

Caterpillar Tractor Co., San Leandro, California

            The Caterpillar Twenty tractor has the distinction of being the first tractor to be designed by the Caterpillar Tractor Co. In early 1926, shortly after C.L. Best Tractor Co. Absorbed the Holt Manufacturing Company to become the Caterpillar Tractor Co., design work on this twenty horsepower machine began at the factor in San Leandro.  In 1927, two Caterpillar Twenty tractors were built as experimental models.  The tractors were built specifically to test the tractor’s design, and after fixing the design flaws they were put into production in October 1927, replacing the Caterpillar 2 Ton tractor. 


Caterpillar Twenty Tractor

Caterpillar Tractor Co., San Leandro, California

             This Caterpillar Twenty Tractor was the first tractor produced by the Caterpillar Tractor Co.  Early tractors designed by the Caterpillar Tractor Co. were gray in color, and it was not until 1931 that the standard color for Caterpillar tractors became yellow.


The Caterpillar Tractor Co. marketed the Caterpillar Twenty as new in size, rating, price, and that the design drew upon the combined experience of the newly merged Best and Holt companies.  The Caterpillar Twenty was popular, and were manufactured until 1933.

The tractor on display here is one of the two models used to test the strengths and weaknesses of the Caterpillar Twenty Tractor’s design. These tractors were run for many days at the testing grounds of the San Leandro factory. One of the tractor test operators was fifteen year old Dan G. Best, son of C.L. Best, who was at the time the chairman of the board of the Caterpillar Tractor Co.


Teenage Dan was given a tractor and told to do whatever he could to stress the machine to its limits and discover what faults might exist. After redesign of the weak points, the Twenty began production in late 1927 replacing the Caterpillar 2 Ton tractor. While the whereabouts of the other Twenty Experimental tractor is unknown, this tractor was used for a time on C.L. Best’s Diamond B ranch at Livingston, California. The same tractor was later given to Dan G. Best, who used it for a few years at his Woodland, California ranch and then parked it.


Caterpillar Model Sixty

With the formation of the Caterpillar Tractor Co. in 1925, the Best Model Sixty was renamed the Caterpillar Model Sixty. Only minor changes, such as fuel tank, manifolds and seat, were made to the Sixty after 1925. With a total of 18,948 tractors produced by both Best and Caterpillar, this tractor was pivotal in the success of both the C.L. Best Tractor Co. and the Caterpillar Tractor Co. This model remained in production by Caterpillar until 1931.


Caterpillar Diesel 60 1C2

A diesel engine was one of the innovations that C.L. Best thought made for a perfect track-type tractor. After the Caterpillar Tractor Co. was formed in 1925, C.L. Best and his engineers began a quest to build a Diesel engine. That Diesel engine became a reality in 1931 and was paired with a reinforced Sixty running gear.


            The Caterpillar Diesel 60 1C2 was one of the first practical Diesel-powered track-type tractors manufactured. This particular tractor was the second in the Diesel-powered series offered by Caterpillar, and was engineered and manufactured in San Leandro, California. Caterpillar Diesel 60 1C2 was destined to stay in the Woodland, California area.  It was first sold to W.C. Schuder who farmed 2000 acres south of Woodland, California, then to Clarence Danielson, J.J. Stephenson, and finally to Fred C. Heidrick Sr., who placed the tractor in the care of the museum.


Track-type tractors forever changed California history.  The influx of track-type tractors made farming California soil much easier, and really allowed agriculture to boom in the state.  Today, Caterpillar is one of the world’s largest producers of tractors, and the company can trace its success in part to the success of track-type tractors in California. 


“Between 1890 and 1914, the California farm economy fundamentally and swiftly shifted from large-scale ranching and grain-growing operations to smaller-scale, intensive fruit cultivation.  By 1910, the value of intensive crops equaled that of extensive crops, as California emerged as one of the world’s principal producers of grapes, citrus, and various deciduous fruits.”[1]




[1] Alan L. Olmstead and Paul W. Rhode, “The Evolution of California Agriculture, 1850-2000,” 3.

[1] The Caterpillar Story, Caterpillar Inc. (Peoria, IL: Caterpillar Inc., 1990), 25. 

[2] Russell Jones, Caterpillar: Album Number One (Perth: Vintage Tractor Publications, 1983), 1-2. 

[3] Caterpillar Sixty: Photo Archive, edited by P.A. Letourneau (Minneapolis, MN: Iconografix, 1993), 9. 

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