What is caterpillar d6 9u years made?

The Caterpillar D6 9U model was produced from 1947 to 1959. It was a bulldozer that was commonly used for construction, mining, and agricultural purposes. The machine weighed around 18,000 pounds and featured a 70 horsepower engine. The D6 9U was designed to work in challenging terrain and was known for its durability and reliability. Many of these bulldozers are still in use today, demonstrating the longevity and quality of Caterpillar machines.