GMC 2007 Sierra - Manual (Page 540)

A. Stoplamp/Taillamp
B. Turn Signal Lamp
C. Back-up Lamp
D. Sidemarker Lamp
Taillamps (Chassis Cab Models)
A. Turn Signal Lamp
B. Taillamp/Stoplamp
C. Back-up Lamp
To replace one of these bulbs, do the following:
1. Peel the rubber seal away from the lens.
2. Lift the lens off the lamp assembly.
3. Pull the old bulb straight out from the socket.
4. Install a new bulb into the socket and
press it in until it is tight.
5. Reinstall the lens and the lens seal.
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