Reverse

Reverse:

REVERSE

When the gear selector lever is moved to the Reverse position, the manual valve blocks line fluid pressure from entering the Drive, D 321, D 2-1, and lo fluid circuits. These fluids exhaust at the manual valve. The manual valve allows line fluid pressure to enter the REV, PRN, PRND43, and PRND4 hydraulic circuits.

^ Manual Valve: In the Reverse range, line pressure from the pressure regulator valve is directed as REV, PRN, PRND4, and and PRND43 fluid pressures at the manual valve. The REV fluid pressure is directed to the #9 checkball, Direct clutch, 1-2 shift valve, and the Pressure Regulator Boost Valve. The PRN fluid is directed to the 3-4 shift valve, the PRND4 fluid is directed to the Pressure Switch Manifold (PSM) and 2-3 shift valve, and the PRND43 fluid is directed to the PSM and the front servo.
^ Pressure Switch Manifold (PSM): REV, PRND4 and PRND43 fluid pressures from the manual valve are directed to the respective switches on the PSM, this sends a signal to the Powertrain Control Module (PCM) that the transmission is in reverse.
^ Solenoid "A": Energized, signal "A" pressure forces the 1-2 shift valve to the extreme left.
^ Solenoid "B": De-energized, exhausting signal "B" fluid through the solenoid.
^ 1-2 Shift Valve: Held to the extreme left by signal "A" fluid pressure. REV fluid pressure from the 1-2 shift valve is directed to and seats the #7 checkball, then to the rear servo which applies the rear band.
^ 2-3 Shift Valve: Is held to the extreme right by spring force. This blocks the PRND4 fluid pressure at the 2-3 shift valve which will be utilized in other gear ranges.
^ 3-4 Shift Valve: Is forced to the extreme right by PRN fluid pressure.
^ Rear Servo: REV fluid pressure from the 1-2 shift valve is directed to and seats the #7 checkball, the fluid flows through an orifice, (which then becomes Rear Band Apply (RBA) fluid pressure) through the case into the rear servo which applies the rear band.
^ #9 and #11 Checkballs: REV fluid pressure from the manual valve is directed to and seats the #9 checkball, this causes the fluid to flow through an orifice (which then becomes 3rd REV fluid pressure) and seats the #11 checkball, and into the direct clutch.
^ Direct Clutch: 3rd REV fluid pressure is directed through the case, the center support and into the direct clutch inner piston area, REV fluid pressure is directed to the direct clutch outer piston. The combination of these two pressures apply the direct clutch. Using both fluid pressures on an increased area of the piston increases the holding capacity of the clutch.