Park Position

Fig 1: Identifying Park Position Components

Courtesy of FORD MOTOR CO.

Mechanical Operation -   Apply components:

• Park pawl engaged, holding the final drive assembly stationary
• Low/reverse clutch applied

Planetary Gearset Operation -   Front planetary gearset driven components:

• None

Center planetary gearset driven components:

• Sun gear

Rear planetary gearset driven components:

• None

Front planetary gearset held components:

• Planetary carrier assembly (splined to final drive assembly, held stationary by park pawl)

Center planetary gearset held components:

• Center ring gear (splined to rear planetary carrier)

Rear planetary gearset held components:

• Planetary carrier
• Rear ring gear (splined to front carrier)

For component information, refer to Mechanical Components and Functions .

Fig 2: Park Position Power Flow

Courtesy of FORD MOTOR CO.

Hydraulic Operation -   Line pressure hydraulic circuits:

• Line pressure from the pump is supplied to the low/reverse/overdrive (4, 5, 6) regulator valve.
• Line pressure is regulated by the pressure regulator valve.
• The pressure regulator valve is controlled by varying pressure from the LPC solenoid through the LPC circuit.

Torque converter circuits:

• Regulated line pressure from the pressure regulator valve is directed to the TCC control valve through the CONV FD hydraulic circuit.
• When the TCC is released, CONV FD pressure is directed to the TCC RELEASE circuit by the TCC control valve. Pressure from the TCC RELEASE circuit releases the TCC.
• Fluid from the TCC RELEASE returns to the TCC control valve through the TCC APPLY circuit.

Cooler and lubrication hydraulic circuits:

• The TCC control valve directs fluid from the TCC APPLY circuit (return circuit from the torque converter when the TCC is released) to the COOLER FEED circuit.
• In the COOLER FEED circuit, transmission fluid flows through the transmission fluid cooler or the thermal bypass valve to the LUBE circuit.

Solenoid hydraulic circuits:

• The LPC solenoid applies varying pressure to the pressure control valve through the LPC hydraulic circuit. The LPC solenoid regulates line pressure by controlling the position of the pressure regulator valve.
• SSD applies pressure to the low/reverse/overdrive (4, 5, 6) regulator valve to apply the low/reverse clutch.
• SSE applies pressure to the multiplex shift valve to position the valve against the spring and direct regulated CBLR/C456 SUPPLY pressure to the low/reverse clutch.

Clutch hydraulic circuits:

• Line pressure from the pump is supplied to the low/reverse/overdrive (4, 5, 6) regulator valve.
• Regulated line pressure from the low/reverse/overdrive (4, 5, 6) regulator valve is sent to the multiplex shift valve assembly through the CBLR/C456 SUPPLY hydraulic circuit.
• The multiplex shift valve directs the fluid to the low/reverse clutch through the CBLR hydraulic circuit.

For additional hydraulic circuit information, refer to Hydraulic Circuits .

Electrical Operation -   Solenoid operation:

Fig 3: Identifying 6F50 Park Position Pressure Circuits

Courtesy of FORD MOTOR CO.

Fig 4: Identifying 6F50 Reverse Position Components

Courtesy of FORD MOTOR CO.