Building a pulling tractor from a garden tractor requires modifications to the engine, transmission, wheels and small components. Pulling tractors are generally diesel and run as high as 7,000 rpm as opposed to 2,000 rpm for a garden tractor. Depending on class, pulling tractors run between 200 and 3,000 horsepower and may need to be weighted down to compete. This extra strain necessitates high-performance parts, titanium or aluminum gears, turbochargers and high quality fuels.
High-performance parts are available from tractor manufacturers such as John Deere and International Tractor directly or on eBay. Competitive tractor pulling is a popular pastime and the community offers detailed instructions for upgrading specific tractors on websites such as GardenTractorPullingTips.com.
To rebuild the engine add turbochargers, an aluminum engine block, aluminum valve heads, a racing fuel delivery system and high-performance pistons. Replace the camshaft and crankshaft. Rebuild the carburetor, and replace the stock head with a new head that is machined for high compression.
Replace the tires with super lug tires for the rear. Ideally, the rear tires can bear most of the weight for the pull with the front tires barely touching the ground. Pulling tires need to roughly match the stock tires on a garden tractor in width and size.
Tractor pulling is an expensive hobby that can run in excess of $20,000 for the tractor upgrade before considering transportation costs for competition.