The horsepower rating of a Wheel Horse tractor varies depending on the model and year of make. As of 2015, the various Wheel Horse tractor models have a rating between 2 and 20 horsepower.
The RJ-25 Wheel Horse tractor generates up to 2 horsepower and was produced in 1955. The most powerful Wheel Horse tractor models are the 270-H, 420, 520-H and 520-8, all four of which generate 20 horsepower. The first Wheel Horse tractor was developed by Elemer Pond in 1946. The brand was purchased by Toro in 1986, and the company continued to produce tractors under the Wheel Horse brand until 2007.