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Transmission Component and System Description

Transmission Component and System Description
The mechanical components of this unit are as follows:
^ A torque converter with a Torque Converter Clutch (TCC)
^ A drive link assembly
^ Intermediate/4th and Lo/Reverse friction band assemblies
^ Forward, Coast, 2nd, Reverse, and Direct multiple disc clutch assemblies
^ Two planetary gear sets: Input and Reaction
^ Two roller clutches (Lo and 2nd)
^ One sprag clutch
^ One vane type oil pump
^ One control valve assembly
^ A final drive and differential assembly

The electrical components of this unit are as follows:
^ Two shift solenoid valves, 1-2 and 2-3
^ A Torque Converter Clutch Pulse Width Modulated (TCC PWM) solenoid valve
^ A transmission Pressure Control (PC) solenoid valve
^ An automatic Transmission Fluid Temperature (TFT) sensor
^ Two speed sensors: input and output speed sensor
^ An automatic Transmission Fluid Pressure (TFP) manual valve position switch assembly
^ An automatic transmission wiring harness assembly
^ A park/neutral position switch

Adapt Function
Transmission Adapt Function The 4T40-E transmission uses a line pressure control system, which has the ability to continuously adapt the system's line pressure. This compensates for normal wear of the following parts:
^ The clutch fiber plates
^ The seals
^ The springs
The PCM maintains the Upshift Adapt parameters for the transmission. The PCM monitors the AT ISS sensor and the AT OSS during commanded shifts in order to determine if a shift is occurring too fast or too slow. The PCM adjusts the signal from the transmission pressure control solenoid in order to maintain a set shift feel.
Transmission adapts must be reset whenever the transmission is overhauled or replaced. In order to reset transmission adapts, select the following:
1. Tech 2
2. Special Functions
3. Transmission Output Controls
4. Clear TAPS