These were very popular tractors and sold extremely well. In production for six years as the 2H series, the RD6 lost the “RD” from its name about 1938.Ī favourite on the jobsite, farm or forest, many thousands of this type were manufactured.Īn improved D6 was introduced in 1941 just in time for World War 2 and for the first time the machine was also available in a wider 74 inch track gauge due to customer requests.īoth the 60 inch gauge D6 (4R series) and 74 inch gauge D6 (5R series) were powered by the new Caterpillar D468 6-cylinder diesel engine which produced 72 flywheel horsepower. With a track gauge of 60 inches and a 5-roller track frame, the RD6 was powered by a 3-cylinder Caterpillar D6600 diesel which put out 52 flywheel horsepower. The following year with a slight horsepower tweak, the machine was re-introduced as the Diesel 40, and in 1935, in order to comply with Caterpillar’s new machine identification system, it became the RD6.

The Caterpillar D6 can trace its origins right back to the Diesel 35 of 1933 when it was one of a trio of Caterpillar diesel tractors introduced during that year (the other machines were the Diesel 50 and the Diesel 70).Īlthough it was in production for only one year, it sowed the seeds for what was to come. Here is an overview of how things got started. For over 80 years, the Caterpillar D6 has been the backbone of the medium size Cat track type tractor range.

D6c caterpillar specs