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. Oldsmobile 260/307/350/394/400/403 and 455 engines - Melling High Volume Oil Pump.