Dakota 2WD V6-3.9L VIN X (1997)
Torque Converter: Description and Operation
GENERAL INFORMATION
The torque converter is a hydraulic device that couples the engine crankshaft to the transmission. The torque converter consists of an outer shell
with an internal turbine, a stator, an overrunning clutch, an impeller, and an electronically applied converter clutch. Torque multiplication is
created when the stator directs the hydraulic flow from the turbine to rotate the impeller in the direction the engine crankshaft is turning. The
turbine transfers power to the planetary gear sets in the transmission. The transfer of power into the impeller assists torque multiplication. At low
vehicle-speed, the overrunning clutch holds the stator stationary (during torque multiplication) and allows the stator to freewheel at high vehicle
speed. The converter clutch engagement reduces engine speed. Clutch engagement also provides reduced transmission fluid temperatures. The
torque converter hub drives the transmission oil (fluid) pump.
The torque converter is a sealed, welded unit that is not repairable and is serviced as an assembly.
CAUTION: The torque converter must be replaced if a transmission failure results in large amounts of metal or fiber contamination in the fluid.
CONVERTER DRAINBACK VALVE
The drainback valve is located in the transmission cooler outlet (pressure) line. The valve prevents fluid from draining from the converter into the
cooler and lines when the vehicle is shut down for lengthy periods. Production valves have a hose nipple at one end, while the opposite end is
threaded for a flare fitting. All valves have an arrow (or similar mark) to indicate direction of flow through the valve.
