The Chevrolet Avalanche is known for the plastic body cladding that covers the bottom half of its exterior. However, not all models are equipped with the cladding. All Avalanches, however, are equipped with daytime running lights (usually referred to as DRLs). The location and position of the DRLs differ between vehicles with body cladding and those without. On Avalanche models with body cladding, the DRL has its own lens assembly; on models without body cladding, the DRL is incorporated into the turn signal assembly. Both models use the same replacement bulb.
Turn the engine off and open the bonnet. Locate the "L"-shaped metal pin behind the headlight assembly.
Turn the pin up, and then pull it straight out (it's mounted horizontally). Carefully hold the headlight assembly and pull it out of its mount. Unplug the two electrical connectors from the rear of the assembly. Set the headlight assembly down in a safe place.
Locate the retaining clip behind the turn signal/daytime running light assembly. Depress the clip to remove the assembly from its mount. Pull it straight toward you to access its rear.
Press the release lever located behind the daytime running light bulb. There are three bulbs in this assembly; the daytime running light is the outboard bulb (closest to the fender well). Turn the bulb clockwise to release it from the assembly.
Detach the old bulb from the socket. Insert the new bulb, and then insert the socket back into the assembly. Turn it clockwise to tighten it. Re-insert the assembly back in place. Push it firmly; you'll hear a snap as it locks back in place.
Connect the electrical connections to the rear of the headlight assembly. Re-insert the assembly into its mount, and then replace the metal pin. Twist the pin's handle down to secure the headlight assembly.
Turn the engine off. Access the front of the Avalanche and get on the ground.
Reach your hand underneath the front fascia. Feel around for the daytime running light socket (don't confuse it with the fog light, which is close by). The daytime running light is square; the fog light is oval.
Turn the daytime running light socket counterclockwise to unhook it from the assembly. Pull the old bulb from the socket, then insert a new bulb. Re-insert the socket into the rear of the assembly; twist it clockwise to tighten it.
Always wear gloves when replacing automotive bulbs. The oils from your skin can cause damage to the bulbs.