GMC 2001 Savana - Manual (Page 81)

2-4
Swing-Out Windows
Side Swing - Out Window
To open the side door swing - out windows, pull up on
the latch at the edge of the window. Swing the window
out and push down on the latch to lock the window
into place.
To close the window, pull the latch toward you and push
down on the latch to lock it.
Rear Swing - Out Window
The rear swing - out windows work the same way, but the
latch is at the bottom edge of the window.