aFe Large Bore 4" HD Diesel Exhaust System w/o Tip (409 Stainless Steel) - 01-05 GM Duramax LB7/LLY (Cat-Back) - 49-14001

AFE Exhaust Systems are designed to replace the original equipment unit on your Diesel Truck. The AFE Large Bore 4 inch HD Diesel Exhaust System adds up to 5 horsepower, increases torque and flow, improves your fuel economy, no welding required, 4"" mandrel bent tubing, smooth bends, and adjustable hangers. AFE's large bore exhaust is dyno proven to increase power and reduce EGT. AFE Large Bore Diesel Exhaust System has mandral bends. Mandrel bends don't squash the tube like OE bends do. They are more painstaking to manufacture but worth it when you want the best for your truck.