2007 Chevrolet Avalanche Owner's Manual - Page 190

Cargo Area Floor Drains Top-Box Storage Your vehicle also has four cargo-area floor drains located under the cargo mat near the sides of the cargo area. These drains should be cleaned periodically to allow water to drain from the cargo area. The cargo mat has cutouts for the drains. Flush the drains through the cutouts. If the cargo area is extremely dirty lift up the edges of the cargo floor mat or take the whole mat out and flush the drains with water. 190 Your vehicle is equipped with top-box storage units on both side of the vehicle. The passenger side top box contains the tools you will need to change a flat tire. Use the ignition/door key to unlock/lock it. Press the key cylinder button and swing the lid open. Turn on the cargo lamps, if equipped, if you need more light inside. See Exterior Cargo Lamps on page 217 for more information.