When the gear selector lever is moved to the REVERSE (R) position (from the PARK position) the following changes occur in the transmission's hydraulic and electrical systems.
Increases (or decreases) in line pressure is primarily influenced by changes in the throttle position as a result of the changing operating conditions of the vehicle.
Is moved manually to the right through the gear selector lever and allows line pressure to enter the reverse fluid passage through the PRN fluid passage.
Located in the control valve body, (300), it blocks the reverse servo feed passage forcing reverse fluid through an orifice in the spacer plate (370) into the reverse servo passage. When the manual valve (404) is moved out of reverse, the ball check valve unseats allowing reverse servo fluid to exhaust through the ball seat instead of through the orifice.
Applies the reverse band (615) in response to reverse servo fluid pressure feeding into the servo cover (40) side of the reverse servo piston (44).
Wraps around the second clutch housing (617) and holds the input carrier (672), through the reverse reaction drum (669), allowing the vehicle to move in reverse.
Remains applied from PARK to REVERSE and becomes effective as the reverse band applies. The input sprag holds at this time.
Line pressure at the valve enters the converter feed circuit which is then routed to the TCC control valve.
Spring pressure holds the valve in the released position. Converter feed fluid is directed to the release circuit. Release fluid seats #1 ball check valve and feeds the TCC blow-off. Release fluid feeds the TCC on the cover side of the pressure plate, exits the TCC through the apply circuit, then feeds the cooler circuit at the TCC control valve. Cooler fluid passes through the ball check valve, through the cooler, then returns to the transmission and feeds the rear lube circuit. A front lube circuit is fed from orificed line pressure.