Apply Components
Apply ComponentsShift Elements
NOTE: All friction and steel clutch plates use a wave designed plate.
In addition to the torque converter, the other shift elements are:
^ three rotating multi-plate clutches: forward, direct and overdrive.
^ two fixed multi-disc brakes: intermediate and low/reverse.
All gear shifts from 1st to 6th or from 6th to 1st are power-on overlapping shifts. That is, during the shift of the clutches must continue to transmit the drive at lower main pressure until the other clutch is able accept the input torque.
The shift elements, clutches or brakes are engaged hydraulically. The transmission fluid pressure builds up between the cylinder and the piston, pressing the clutches together.
The purpose of these shift elements is to carry out in-load shifts with no interruption to traction.
Multi-plate clutches, forward, direct and overdrive supply power from the engine to the planetary geartrain. Multi-disc brakes intermediate and low/reverse press against the transmission housing in order to achieve a torque reaction effect.
Multi-Plate Clutch
Clutches overdrive, forward and direct are balanced in terms of dynamic pressure. That is, its piston is exposed to the transmission fluid flow on both sides, in order to prevent pressure buildup in the clutch as speed increases. This equalization process is achieved by a baffle plate and pressure-free transmission fluid supply by a lubricating passage, through which the space between piston and baffle plate is filled with transmission fluid.
The advantages of this dynamic press-are equalization are:
^ reliable clutch engagement and release in all speed ranges.
^ improved shift refinement.
Shift Overlap Control
The electro-hydraulic shift action is obtained by means of various valves in the transmission control module (TCM) and main control valve body, actuated by pressure regulators. They engage or disengage the relevant clutches, or brakes at the correct moments.
Hydraulic Systems
Fluid Pump
The torque converter is supported in the fluid pump by a needle roller bearing. The fluid pump is driven directly from the engine by the torque converter shell and supplies transmission fluid to the transmission and the hydraulic control unit.
The fluid pump draws in transmission fluid through a filter and delivers it at high press-are to the main pressure valve in the main control valve body unit.
The valve adjusts the pressure and returns excess transmission fluid to the fluid pan.
Fluid Filter
All transmission fluid that is picked up from the pan passes through the fluid filter. The filter and its accompanying seal are part of the fluid path from the pan to the fluid pump.