Intermediate and Fourth Servo
WARNING: This page is about a different car, the 2010 Pontiac G5 and 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
Intermediate band fluid exhausts from the servo piston. A spring force moves the piston and the apply pin, and the intermediate and fourth band releases. However, the intermediate and fourth band remains applied in Manual First - Second Gear in order to achieve engine compression braking.