This Fits Your 2003 GMC Sierra 2500 HD 6.0L Vortec V8 A/T RWD WT Standard Cab Pickup Fleetside
Full size assembly image of EMISSION SYSTEM. EMISSION COMPONENTS. (1/1)

EMISSION SYSTEM. EMISSION COMPONENTS.

4. 3 liter. 4. 8 liter. 5. 3 & 6. 0 liter. 5. 3 & 8. 1 liter. 5. 3 liter. 6. 0 & 8. 1 liter. 6. 6 liter diesel. Front. Gas. Rear.