Melling is the leader in oil pump engineering, prototyping, and production. Melling specializes in several different styles of oil pumps including: Variable Displacement Oil Pumps, Vane Oil Pumps, Cast Iron Oil Pumps, Gerotor Oil Pumps, Aluminum Oil Pumps, Crescent Gear Oil Pumps, and traditional Spur Gear Oil Pumps. Ford Truck, Mercury - 281,330 (2004-07).