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

In PARK (P) range with the engine running, fluid is pulled from the sump, through the filter (100), and into the oil pump (200). The pressure regulator valve (313) and a decrease passage combine to regulate the pump output. This decrease passage creates a calibrated output pressure called line pressure. In PARK range, line pressure is directed to the following components:

The pressure regulator valve regulates the pump output in response to the following:

The manual valve is manually controlled through the gear selector lever. The valve directs line pressure from the pressure regulator valve (313) into the PRN passage in PARK, REVERSE, or NEUTRAL. The manual valve can also hydraulically override the electronic shift control system in the transmission when you select MANUAL THIRD and MANUAL SECOND gear.

The vacuum modulator controls the modulator valve. This valve regulates modulator pressure inversely to engine vacuum. Modulator pressure is directed to the following:

In PARK range, line pressure passes through the 2-3 shift valve (357) and line pressure feeds the input clutch feed passage. Line pressure then passes through the 3-4 shift valve (362) and around the #3 checkball (372, located in the channel plate) in order to apply the input clutch. Although the input clutch is applied and the input sprag is holding, these conditions are not effective because neither the forward band assembly (688) nor the reverse band assembly (615) is applied.

Line pressure and spring force hold the torque converter clutch solenoid (TCC Sol.) valve against the torque converter clutch solenoid (315). This provides converter feed pressure to the release side of the converter clutch pressure plate. In this position, converter clutch applied pressure feeds into the cooler passage, through the cooler, and into the lube circuit.

The converter clutch regulator valve is biased by the modulator and by pressure from the TCC accumulator. The valve uses line pressure to provide regulated applied fluid to the converter clutch valve (335) in those applications that do not use a Pulse Width Modulator (PWM).

The Powertrain Control Module (PCM) electrically controls the PWM solenoid. The PCM regulates PWM feed pressure through the PWM passage to the converter clutch regulator valve (330). This arrangement precisely controls the amount of regulated applied pressure from the converter clutch. Because the PWM solenoid (325) is not energized until Third gear operation, full line pressure passes through the solenoid to the converter clutch regulator valve (330).

The Powertrain Control Module (PCM) controls the 1-2 shift solenoid valve. The solenoid is energized (turned ON) in PARK range. Line pressure moves the 1-2 shift valve (318) against a spring pressure which directs line fluid into the 1-2 shift solenoid valve passage. Then the 1-2 shift solenoid valve fluid is directed to the 3-4 shift valve (362).

The Powertrain Control Module (PCM) controls the 2-3 shift solenoid valve. The solenoid is energized (turned ON) in PARK range and the solenoid directs line pressure into the 2-3 shift solenoid valve passage. Then the 2-3 shift solenoid valve fluid is directed to the following:

The pressure relief valve exhausts line pressure above 1690-2480 kPa (450-360 psi).

The line pressure tap allows line pressure to be monitored with a gage.