Intermediate and Fourth Band Releases

WARNING: This page is about a different car, the 2007 Pontiac G5 Pursuit, 2007 Pontiac G5, and 2007 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

1-2 Shift Solenoid Valve

The PCM de-energizes the normally open solenoid valve and the 1-2 signal fluid exhausts.

3-4 Shift Valve

The 1-2 signal fluid pressure exhausts from the 3-4 shift valve and a spring force moves the valve into the Third gear position. This opens the Fourth band fluid circuit to an orificed exhaust in order to help control the band release.

Intermediate and Fourth Servo

Fourth band fluid exhausts from the servo and a spring force moves the servo to the release position, thereby releasing the band.

3-4 Accumulator

The fourth band fluid exhausts from the accumulator. A combination of spring force and 3-4 accumulator feed fluid pressure moves the accumulator piston to the Third gear position.

1-2/3-4 Accumulator Valve

The accumulator valve regulates line pressure into the 1-2/3-4 accumulator fluid circuit in order to fill the 3-4 accumulator. Torque signal fluid pressure controls this regulation. Increased torque signal fluid pressure regulates accumulator fluid to a higher pressure.