Cummins 6C/ISC 3978522 Exhaust Manifold PAI 181052CROSS REFERENCE: 3978522 3931440 3907451 APPLICATION: Cummins 6C ISC BRAND: PAI 181052 Cummins 3978522 Exhaust Manifold PAI 181052 intended for heavy truck parts and truck engine parts. Provides stable exhaust flow. Prevents leaks. Maintains consistent system efficiency. All components are proudly manufactured in the U. S. A. by PAI Industries Inc., an ISO9001 certified company with over 50 years of experience in the heavy duty truck parts industry.