For a view of the oil flow diagram, refer to the 1996 TURM Manual.

A manual 4-3 downshift is accomplished by moving the gear selector lever to the Manual Third (3) position. In Manual Third the transmission is hydraulically prevented from upshifting into Fourth gear under any conditions. Also, the coast clutch is applied in all manual ranges in order to provide engine compressing braking whenever appropriated. The following information explains the additional changes during a Manual 4-3 downshift as compared to a forced 4-3 downshift. Refer to Overdrive Range, 4-3 Downshift - Torque Converter Clutch Not Applied for a complete description of a 4-3 downshift.

Fourth Gear Hydraulically Prevented

Manual Valve: The manual valve moves into the Manual Third (3) position and line pressure enters the D321 fluid circuit. Also the manual valve blocks line pressure from the PRND4 fluid circuit and the PRND4 fluid exhausts past the manual valve.

3-4 Shift Valve: D321 fluid pressure assists a spring force in order to keep the valve in the Third gear position under any conditions. this opens the Forth band fluid circuit to an orificed exhaust and the Intermediate and Fourth band releases, thereby preventing Fourth gear.

Important: The operating states for the shift solenoids follow the normal operation depending on vehicle driving conditions

A/T Fluid Pressure Manual Valve Position Switch (TFP Val. Position Sw.) Assembly: PRND4 fluid exhausts from the TFP Val. Position Sw. Assembly, which signals to the PCM that the manual valve is in the Manual Third position.

Coast Clutch Applies

3-4 Shift Valve: D321 fluid is routed through the 3-4 shift valve and into the coast clutch fluid circuit.

Coast Clutch: Coast clutch fluid pressure applies the coast clutch. With the coast clutch applied, engine compression braking is available in Manual Third - Third Gear in order to slow the vehicle when the throttle is released.

Manual Third -- Second and First Gears

The transmission operates the same in Manual Third as in Overdrive range with the exception that Fourth gear is prevented. The transmission will upshift and downshift between First, Second, and Third gears as in Overdrive range. However, engine compression braking is not available in Manual Third - First and Second gears, and the vehicle will coast when you release the throttle.