Fill Tube Plug Replacement
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, 2003 Chevrolet Cab & Chassis Silverado, and 2002 GMC Sierra. However, it is still accessible from the selected car via links, so may be relevant.
Remove fill tube plug for main housing. Remove fill tube seal. Install fill tube seal into main housing. Align tab on fill plug with tang on main housing. Install fill plug into fill tube seal (fill plug should click into place). Install plug tab into main housing tang.