Excessive Shift Shock When Upshifting or Downshifting

EXCESSIVE SHIFT SHOCK WHEN UPSHIFTING OR DOWNSHIFTING
1. Fluid level too low or fluid contaminated.
2. Incorrectly adjusted throttle cable.
3. Malfunctioning control valve(s).
4. Defective accumulator(s).
5. Defective coasting clutch.
6. Defective 3-4 clutch.
7. Defective 2-4 brake band and/or servo.