Chevrolet Avalanche Owner's Manual page 86

4. With the rear glass tilted toward you, lift it out from
the lower window frame channel. Use the grab
handles to assist you in removing the rear glass.
2-16
5. Load the rear glass into the storage pocket in the
midgate, guiding the lower edge of the rear glass
behind the three rear glass retaining tabs (E).
Hold the rear glass flat against the storage pocket,
with grab handles facing you, until the next step.