Please check notes in each part listing to ensure the Heater Fitting is correct for your 2003 GMC SIERRA 1500 with a 4.8L engine. Special restrictions like "California only" or "with sport package" may indicate a Heater Fitting fits only certain 2003 GMC SIERRA 1500 models.
Clicking a "More Info" link will display a picture and/or other details about that Heater Fitting in a separate window (you may need to turn off your pop-up-blocking software for this to work).
After choosing a Heater Fitting, click the "Add Part" button. Shipping costs will be shown on the Shopping Cart page. You may use your browser's Back button or click "Find More Parts" to find more Heat & Air Conditioning parts, other GMC SIERRA 1500 parts or parts for a different vehicle. Please try our Interactive Catalog (click link above) for faster searching. Both catalogs use the same shopping cart so any auto parts you've already chosen for your 2003 GMC will not be lost if you switch.
