It is located behind the headlight bezel on the drivers side of the truck. Kind of a pain to get to. But the easiest way to get to it is to remove the grille, and then the headlights. You should see it towards the bottom.
The 2003 GMC Sierra-2500HD has 16 valves.
The 2003 GMC Sierra-1500 has 12 valves.
The 2003 GMC Sierra-1500 has a V6 engine.
The 2003 GMC Sierra-2500HD has a V8 engine.
The 2003 GMC Sierra-1500 is a gas-powered vehicle.
The 2003 GMC Sierra-2500HD is a gas-powered vehicle.
The 2003 GMC Sierra-1500 has overhead valves (OHV).
The 2003 GMC Sierra-2500HD has overhead valves (OHV).
The 2003 GMC Sierra-1500 has a 5-speed manual.
The 2003 GMC Sierra-2500HD has a 5-speed manual.
YES.
The height of the 2003 GMC Sierra-2500HD is 6 ft. 4.2 in. (76.2 in.).