Bully Dog was formed in 1998 in Aberdeen, Idaho. The founders of Bully Dog – Michael, Phillip, and Daryl Klassen were heavily influenced by their father Harold’s interest in improving vehicle performance. Several years prior to the company’s inception, Harold had experimented with increasing performance on his diesel farm tractor by injecting propane into the engine’s combustion chamber.

In 1998, Bully Dog’s owners took this concept and developed and patented a safe and effective propane injection system to enhance diesel engine performance. These systems were first sold out of their farm shop, but as demand increased, the owners moved their company to another location and officially organized Bully Dog.

Bully Dog’s quest was now to be recognized as the leader in the diesel performance industry, which motivated them to stay abreast of new technology in this industry. With the introduction of electronic components and software to improve performance, they began to research new types of products like intake and exhaust systems to complement their electronic components. Bully Dog was now able to offer a complete performance package.

In 2005, the company expanded its range of products to include performance products for gasoline powered vehicles.

Bully Dog products are built to be flexible, allowing each user to get their own desired result, from outrageous performance on the race track to improved fuel economy driving down the highway.

Each product goes through an in-depth research and development (R&D) followed by a grueling development procedure that is carried out by a staff of the best engineers in the world. Once designed, each product is put through months of real world testing, this testing is performed across the United States so that Bully Dog can be sure that each product works correctly and flawlessly in various elevations, weather conditions and driving situations from towing a heavy load to racing down the track.

Bully Dog products have been featured in countless media venues, including a Dodge Ram build-up covered by Trucks! on the Speed Channel. That truck also featured the exclusive Andy's Auto Sport Dodge Ram Blaze body kit. The end results was a beast of a truck!