The Model A replaced the GP and became John Deere's first true row-crop tractor. It was produced between 1934 and 1952 solely to compete with the Farmall tractors. The Model A saw many changes along the way including in 1940 when the engine was increased from 309 to 321 cubic-inches and in 1941 when the transmission went from four forward speeds to six. John Deere's Model A tractor was also the company's first to come straight from the factory with rubber tires. John Deere built a total of 300,000 Model A tractors and they sold for about $2400 in 1952.