Description: 1/2 ton, rear floor, crew cab. 4.3L, rear, crew cab. 6.0L. rear floor crew cab. 3/4 & 1 ton, rear floor, crew cab. For Exhaust Muffler. 5.3 & 6.2L. rear crew cab. 6.6L DIESEL. rear floor crew cab. Can help prevent exhaust heat from damaging your vehicle's undercarriage and engine compartment components This GM Genuine Part is designed, engineered, and tested to rigorous standards and is backed by General Motors