Trust your engine will run smoothly and efficiently while on the road with aftermarket Peterbilt 377 engine cooling parts from 4 State Trucks. We know how important it is to keep your engine temperatures under control when traveling long distances for optimum performance. That is why we have a large selection of top quality aftermarket and custom products for your Peterbilt 377. Shop for AC condensers, radiators, coolant reservoirs, and more. Keep your Peterbilt engine cool with help from 4 State Trucks.