Dodge Ram Truck 1500-2500-3500. Manual — part 1808

Once the TCC control valve has moved to the right, line pressure is directed to the tip of the switch valve, forcing
the valve to the right. The switch valve now vents oil from the front of the piston in the torque converter, and sup-
plies line pressure to the (rear) apply side of the torque converter piston. This pressure differential causes the piston
to apply against the friction material, cutting off any further flow of line pressure oil. After the switch valve is shuttled
right allowing line pressure to engage the TCC, torque converter pressure is directed past the switch valve into the
transmission cooler and lubrication circuits.

CONVERTER CLUTCH LOCK-UP VALVE

The torque converter clutch (TCC) lock-up valve controls the back (ON) side of the torque converter clutch. When
the PCM energizes the TCC solenoid to engage the converter clutch piston, pressure is applied to the TCC lock-up
valve which moves to the right and applies pressure to the torque converter clutch.

CONVERTER CLUTCH LOCK-UP TIMING VALVE

The torque converter clutch (TCC) lock-up timing valve is there to block any 4-3 downshift until the TCC is com-
pletely unlocked and the clutch is disengaged.

SHUTTLE VALVE

The assembly is contained in a bore in the valve body above the shift valves. When the manual valve is positioned
in the Drive range, throttle pressure acts on the throttle plug of the shuttle valve to move it against a spring, increas-
ing the spring force on the shuttle valve. During a part or full throttle 1-2 upshift, the throttle plug is bottomed by
throttle pressure, holding the shuttle valve to the right against governor pressure, and opening a by–pass circuit.
The shuttle valve controls the quality of the kickdown shift by restricting the rate of fluid discharge from the front
clutch and servo release circuits. During a 3-2 kickdown, fluid discharges through the shuttle by-pass circuit. When
the shuttle valve closes the by-pass circuit, fluid discharge is restricted and controlled for the application of the front
band. During a 2-3 “lift foot” upshift, the shuttle valve by-passes the restriction to allow full fluid flow through the
by-pass groove for a faster release of the band.

Manual Valve

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BOOST VALVE

The boost valve provides increased fluid apply pres-
sure to the overdrive clutch during 3-4 upshifts, and
when accelerating in fourth gear.

The boost valve also serves to increase line pressure
during torque converter lock-up.

REMOVAL

The valve body can be removed for service without having to remove the transmission assembly.

The valve body can be disassembled for cleaning and inspection of the individual components.

The only replaceable valve body components are:

•

Manual lever.

Boost Valve Before Lock-up

Boost Valve After Lock-up

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•

Manual lever washer, seal, E-clip, and shaft seal.

•

Manual lever detent ball.

•

Throttle lever.

•

Fluid filter.

•

Pressure adjusting screw bracket.

•

Governor pressure solenoid.

•

Governor pressure sensor (includes transmission temperature thermistor).

•

Converter clutch/overdrive solenoid assembly and harness.

•

Governor housing gasket.

•

Solenoid case connector O-rings.

1. Shift transmission into NEUTRAL.

2. Raise vehicle.

3. Remove gearshift and throttle levers from shaft of

valve body manual lever.

4. Disconnect wires at solenoid case connector (1).

5. Remove the transmission range sensor (2) (Refer

to 21 - TRANSMISSION/AUTOMATIC/TRANSMIS-
SION RANGE SENSOR - REMOVAL).

6. Position drain pan under transmission oil pan.

7. Remove transmission oil pan and gasket.

8. Remove fluid filter from valve body.

9. Remove bolts attaching valve body to transmission

case.

10. Lower valve body enough to remove accumulator

piston and springs.

11. Work manual lever shaft and electrical connector

out of transmission case.

12. Lower valve body (1), rotate valve body away

from case, pull park rod (3) out of sprag, and
remove valve body.

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DISASSEMBLY

CAUTION: Do not clamp any valve body component in a vise. This practice can damage the component
resulting in unsatisfactory operation after assembly and installation. Do not use pliers to remove any of the
valves, plugs or springs and do not force any of the components out or into place. The valves and valve
body housings will be damaged if force is used. Tag or mark the valve body springs for reference as they
are removed. Do not allow them to become intermixed.

1. Disconnect wires from governor pressure sensor

and solenoid.

2. Remove screws attaching governor body and

retainer plate to transfer plate.

3. Remove retainer plate, governor body and gasket

from transfer plate.

4. Remove governor pressure sensor from governor

body.

5. Remove governor pressure solenoid by pulling it

straight out of bore in governor body. Remove and
discard solenoid O-rings if worn, cut, or torn.

6. Remove small shoulder bolt that secures solenoid

harness case connector (1) to 3-4 accumulator
housing (2). Retain shoulder bolt. Either tape it to
harness or thread it back into accumulator housing
after connector removal.

7. Unhook overdrive/converter solenoid harness (1)

from 3-4 accumulator cover plate (2)

.

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