Chrysler 2005 Crossfire SRT6 Service Manual page 3416

21 - 346 AUTOMATIC - NAG1 SERVICE INFORMATION
The stator assembly is mounted on a stationary shaft
which is an integral part of the oil pump. The stator (1)
is located between the impeller (2) and turbine (4)
within the torque converter case. The stator contains a
freewheeling clutch, which allows the stator to rotate
only in a clockwise direction. When the stator is
locked against the freewheeling clutch, the torque mul-
tiplication feature of
operational.
TORQUE CONVERTER CLUTCH (TCC)
The TCC was installed to improve the efficiency of the torque converter that is lost to the slippage of the fluid cou-
pling. Although the fluid coupling provides smooth, shock-free power transfer, it is natural for all fluid couplings to
slip. If the impeller and turbine were mechanically locked together, a zero slippage condition could be obtained. A
hydraulic piston with friction material was added to the turbine assembly to provide this mechanical lock-up.
In order to reduce heat build-up in the transmission and buffer the powertrain against torsional vibrations, the TCM
can duty cycle the torque converter lock-up solenoid to achieve a smooth application of the torque converter clutch.
This function, referred to as Electronically Modulated Converter Clutch (EMCC) can occur at various times depend-
ing on the following variables:
• Shift lever position
• Current gear range
• Transmission fluid temperature
• Engine coolant temperature
• Input speed
• Throttle angle
• Engine speed
OPERATION
The converter impeller (driving member), which is integral to the converter housing and bolted to the engine drive
plate, rotates at engine speed. The converter turbine (driven member), which reacts from fluid pressure generated
by the impeller, rotates and turns the transmission input shaft.
TURBINE
As the fluid that was put into motion by the impeller blades strikes the blades of the turbine, some of the energy and
rotational force is transferred into the turbine and the input shaft. This causes both of them (turbine and input shaft)
to rotate in a clockwise direction following the impeller. As the fluid is leaving the trailing edges of the turbine's
blades, it continues in a "hindering" direction back toward the impeller. If the fluid is not redirected before it strikes
the impeller, it will strike the impeller in such a direction that it would tend to slow it down.
the torque converter is
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