The Introduction of the D9 Dozer – 60 Years Ago

When the D9 Dozer was introduced, it had been evolving on Caterpillar drawing boards and at proving grounds for five years. Two pilot machines were built for testing at the Caterpillar Proving Grounds in Phoenix, Ariz. and Washington, Ill. In 1954, Caterpillar sought out direct input from customers during the design of the new tractor when the company built 10 pilot machines and shipped them to multiple customers for testing in different applications.

The first D9 pilot machine was assigned to a logging site in Washington. Nine additional pilot machines were assigned to:

  • Logging jobs in California 
  • Road construction in Ohio, Nevada and Utah
  • Dam construction in South Dakota (Oahe Dam) and California (Cherry Valley Dam)
  • A stone quarry in Michigan
  • A cement company in Illinois 
  • Oil refinery construction in Washington

One of the logging customers testing the machine commented, “The maneuverability of the machine was good considering its size with pioneering and bulldozing production increased considerably over tractors in the 150 drawbar horsepower class. At no time did we find the machine underpowered for the jobs we handed it. Our operators were well satisfied with the comfort of the seat and convenience of controls.” Another logging customer commented that their production increased 50% with the D9 Tractor.

A customer involved in major construction projects commented, “After observing your test model, we have confidence enough in your machine to place orders for 10 current production models.”

Final design of the production model incorporated suggestions from customers involved in the pilot test program. The first production D9 – and the first new track-type tractor produced by Caterpillar since 1938 – came off the assembly line in April 1955. At that time, it was the world’s largest and most powerful tractor, weighing more than 56,000 pounds with a turbocharged 286 horsepower engine. Additional features included a standard or torque converter transmission, oil-type clutch, in-seat starting, excellent operator visibility and many servicing conveniences that were previously not available in Caterpillar’s product line at the time.

Today’s D9, the D9T, has a reputation for outstanding productivity, operator comfort, and robust reliability. It is a highly versatile machine flexible enough to be used in heavy construction, quarries, landfills, forestry, and mine sites. Cat® customers can count on the new D9T’s superior performance, long life, ease of operation and world-class service from the global Cat dealer network to be the backbone of their operation.

D9 Dozer pilot machine at the Peoria Proving Grounds in 1954 D9 Dozer pilot machine at the Peoria Proving Grounds in 1954
A D9 Dozer pilot machine undergoing tests at the Peoria Proving Grounds in Washington, Illinois, 1954.