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Gear Selector Position "D" (Overdrive)

  1. With gear selector in "D" (overdrive) position, steadily increase throttle pressure to accelerate vehicle. Note shift speed engagement points in 2nd gear, 3rd gear and overdrive gear. Use shift speed charts as a reference for correct shift speeds. See Figure-5. Also note when Torque Converter Clutch (TCC) engages while in 3rd gear or overdrive.
    NOTE: Ensure TCC engages in 3rd gear or overdrive during the following steps. Transmission has a Pulse Width Modulated (PWM) solenoid, which may make TCC engagement point hard to detect. If necessary, a scan tool may be used to indicate TCC and shift solenoid operation.
  2. At vehicle speeds of 40-50 MPH, quickly depress accelerator to half open position (part throttle detent downshift). TCC should release, solenoid "A" turns off, and transmission should immediately downshift to 3rd gear.
  3. At vehicle speeds of 40-50 MPH, quickly depress accelerator to wide open position (full throttle detent downshift). TCC should release, solenoids "A" and "B" turn off, and transmission should immediately downshift to 2nd gear.
  4. At vehicle speeds of 40-55 MPH, release accelerator pedal while moving gear selector to "3" (3rd gear) position. TCC should release, transmission should downshift to 3rd gear, and engine braking should slow vehicle.
  5. Move gear selector to "D" (overdrive) position, and accelerate to 40-45 MPH. Release accelerator pedal while moving gear selector to "2" (2nd gear) position. TCC should release, transmission should downshift to 2nd gear immediately, and engine braking should slow vehicle.
  6. Move gear selector to "D" (overdrive) position, and accelerate to 30 MPH. Release accelerator pedal while moving gear selector to "1" (1st gear) position. TCC should release, transmission should downshift to 1st gear, and engine braking should slow vehicle.
  7. With gear selector in "D" (overdrive) position, accelerate vehicle to overdrive gear with TCC applied. Release accelerator pedal, and lightly apply brakes. The TCC should release. Note speeds at which vehicle downshifts. See Figure through Figure.
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