Overdrive Range, First Gear Before First 1-2 Shift

When the shift lever is shifted from Neutral (N) to Overdrive (D) before the first 1-2 shift, the following changes would occur after the transmission shifting to Overdrive - the 1st gear.

Manual Valve: In Overdrive, Manual Valve sends the line pressure to D432 fluid circuits. D432 fluid is sent to 1-2 shift valve and 3-4 shift valve.

#6 and #7 Ball Check Valves: D432 fluid goes against #6 ball check valves and flows into the forward clutch fluid circuits through valve bore #15. D432 fluid also feeds fuel as necessary via a spring loaded #7 Ball Check Valve to help to control the forward clutch apply.

Forward Clutch Assembly: The forward clutch fluid is sent to forward clutch piston to apply Forward Clutch Plate.

#5 Ball Check Valves: The forward clutch fluid goes against #5 ball check valves and flows into coast clutch feed lines through valve bore #17. The valve bore helps to control coast clutch apply.

Safety Mode Valve: The safety mode valve (34) 1 remain the released position to send line fluid pressure to line safety mode fluid circuits.

4-5 Shift Valve: The line safety mode fluid overcomes the 4-5 shift valve (373) spring tension to apply the 4-5 shift valve (374). The operation makes coast clutch feed fluid flows into coast clutch fluid circuits.

Coast Clutch Assembly: The coast clutch fluid is sent to the coast clutch piston to apply coast clutch plate.

2-3 SS Valve: 2-3 SS valve is energized to make the feed limit fluid flow into 2-3 signal fluid circuits. 2-3 signal fluid overcomes spring tension and open 2-3 SS (371).

3-4 SS Valve and 3-4 Shift Valve: 2-3 signal fluid is sent to 3-4 shift control valve (346) and overcomes the spring tension to apply the valve. The operation makes D432 fluid flow into 123 fluid circuits.

#4 Ball Check Valve: 123 fluid goes against the #4 ball check valve and flows through the valve bore #16. The valve bore helps to control Low and Reverse clutch apply.

4-5 Shift Valve: The throttled 123 fluid is sent to 4-5 shift valve (374) and then flows into 123 brake fluid circuits.

Low Pressure Control Valve: 123 brake fluid flows into Low Pressure Control Valve (383). The valve overcomes spring tension and adjusts 123 brake fluid to flow into 123 adjusting fluid circuits, and throttles 123 adjusting fluid pressure.

1-2 SS Valve and 1-2 Shift Valve: 2-3 signal fluid is sent to 1-2 shift control valve (366) and overcomes the spring tension to apply the valve.

1-2 SS Valve and 1-2 Shift Valve: 2-3 signal fluid is sent to 1-2 shift control valve (366) and overcomes the spring tension to apply the valve.

The operation makes the feed limit fluid flow into fluid circuits.

Feed pipe fluid flows into 1-2 shift valve (387) and overcomes spring tension to apply the valve.

123 adjust fluid flows into 1-2 shift valve through valve bore #20 and then flows into Low and Reverse clutch fluid circuits.

The operation makes the feed limit fluid flow into fluid circuits. Feed pipe fluid flows into 1-2 shift valve (387) and overcomes spring tension to apply the valve. 123 adjust fluid flows into 1-2 shift valve through valve bore #20 and then flows into Low and Reverse clutch fluid circuits. #8 Ball Check Valve: Low and Reverse Clutch fluid goes against the #8 ball check valve to the reverse lockout fluid circuits and flows into Low and Reverse Clutch or reverse lockout fluid passages.

Low and Reverse Clutch: Low and Reverse Clutch or Reverse lockout fluid pressure is sent to the outboard area of Low and Reverse Clutch piston, so the piston overcomes the spring tension to apply Low and Reverse Clutch Plate.

1-2 Shift Valve: D432 fluid flows into 1-2 shift valve (387) and is prevented by the valve to be ready to upshift to 2nd gear.

Overdrive Range, First Gear After First 1-2 Shift

When the shift lever is shifted from Neutral (N) to Overdrive (D) after the first 1-2 shift, the following changes would occur after the transmission shifting to Overdrive - the 1st gear.

Manual Valve: In Overdrive, Manual Valve sends the line pressure to D432 fluid circuits. D432 fluid is sent to 1-2 shift valve and 3-4 shift valve.

#6 and #7 Ball Check Valves: D432 fluid goes against #6 ball check valves and flows into the forward clutch fluid circuits through valve bore #15. D432 fluid also feeds fuel as necessary via a spring loaded #7 Ball Check Valve to help to control the forward clutch apply.

#5 Ball Check Valves: The forward clutch fluid goes against #5 ball check valves and flows into coast clutch feed lines through valve bore #17.

Forward Clutch Assembly: The forward clutch fluid is sent to forward clutch piston to apply Forward Clutch Plate.

2-3 SS Valve: 2-3 SS valve is energized to allow the feed limit fluid to flow into the 2-3 signal fluid passage. 2-3 signal fluid overcomes 2-3 shift valve spring (372) tension to move 2-3 shift valve (371) to the applied position.

1-2 Shift Control Valve and 1-2 Shift Valve: 2-3 signal fluid is sent to 1-2 shift control valve (366) and overcomes 1-2 shift control valve spring tension (367) to move the valve to the applied position. The operation makes the feed limit fluid flow into feed pipe fluid circuits. Feed pipe fluid flows into 1-2 shift valve (387) and overcomes 1-2 shift valve spring (388) tension to move the valve to the applied position so as to prevent D432 fluid from flowing into the valve.

3-4 Shift Control Valve and 3-4 Shift Valve: 2-3 signal fluid is sent to 3-4 shift control valve (346) and overcomes 3-4 shift valve spring tension (344) to move the valve to the applied position. The operation makes D432 fluid flow into 123 fluid circuits through 3-4 shift valve (345).

#4 Ball Check Valve: 123 fluid goes against the #4 ball check valve and goes through the valve bore #16. The valve bore helps to control coast clutch apply.

4-5 Shift Valve: The throttled 123 fluid is sent to 4-5 shift valve (374) and then flows into coast clutch fluid circuits.

Coast Clutch Assembly: The coast clutch fluid is sent to the coast clutch piston to apply coast clutch plate.

Fluid Pressure Directed in Preparation for 2nd Gear 1-2 Shift Valve: D432 fluid is sent to 1-2 shift valve (387) and is prevented by the valve in preparation to upshift to 2nd gear.