Active Fuel Management, available on most GM trucks and SUVs, helps lower fuel costs by enabling V8 engines to behave like four-cylinder engines when cruising with light loads, while seamlessly unleashing their full muscle whenever needed. Range AFM Plus works with your factory installed AFM allowing your vehicle to drive in V4 mode up to 80% of the time, maximizing your fuel and dollar savings. The average driver can save approximately 65 gallons of gas per year or about $250.