D-4 - Third Gear

Drive Range - Third Gear:

D-4 - THIRD GEAR

CONVERTER CLUTCH - APPLIED
OVERDRIVE ROLLER CLUTCH - HOLDING
DIRECT CLUTCH - APPLIED
FORWARD CLUTCH - APPLIED

As both vehicle speed and governor pressure increase, the force of governor oil acting on the 2-3 shift valve overcomes the force of the 2-3 Throttle Valve (T.V.) spring and Modulated Throttle Valve (M.T.V.) up oil. This allows the 2-3 shift valve to open and allows RND4D3 oil to enter the 3rd clutch passage.

Third clutch oil from the 2-3 shift valve is directed to the following:
1. 3-2 Exhaust Checkball (4)
2. Third Clutch and Reverse Checkball (6)
3. Inner Piston of Direct Clutch
4. Third Clutch Accumulator Checkball (2)
5. Third Accumulator Exhaust Checkball (7)
6. Intermediate Servo
7. 3-2 Control Valve

BASIC CONTROL

Third clutch oil from the 2-3 shift valve flows past the 3-2 exhaust checkball (4), to the 3rd/reverse checkball (6), seating it in the reverse passage. Third clutch oil then flows to the inner area of the direct clutch piston, applying the direct clutch. At the same time, third clutch oil is directed past the third clutch accumulator checkball (2), seats the third accumulator exhaust checkball (7), and then into the release side of the intermediate servo. This third clutch accumulator pressure combined with the servo cushion spring, moves the servo piston against second oil and acts as an accumulator for a smooth intermediate band release and direct clutch apply.

Third clutch oil flows through the 3-2 control valve to the third clutch accumulator passage.

SUMMARY

The converter clutch is applied*, the overdrive roller clutch is holding, the forward clutch is applied, the direct clutch is applied, and the intermediate band is released; the transmission is in Drive (D) Range - Third Gear (direct drive).

The converter clutch may or may not be applied, depending on shift calibration and solenoid operation.