PTO stands for Power Take Off. Chevy's PTO is a system that allows the engine to power auxiliary equipment, such as a snowplow or winch. The PTO is located on the back of the engine and consists of a shaft that extends to the rear of the vehicle. There is a gearbox attached to the shaft that engages and disengages the PTO. When engaged, the PTO turns on a pump that supplies hydraulic fluid to the equipment being powered by the engine.