For 1990-2009 cars

Check | Causes
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DEFINITION: One of the two following conditions occurs during a 4th to 5th and 5th to 4th gear steady throttle upshift, or a 4th to 5th gear coast, or a light to moderate throttle detent downshift: Harsh shift feel - an unacceptable quick gear change occurs.
Overdrive Clutch and Coast Clutch |

• | Damaged or cut piston

• | Damaged or worn clutch plates

Fluid Pump Assembly |

• | Pressure regulator valve stuck

• | Pressure regulator valve spring

• | Line boost valve spring

• | Line boost valve or bushing stuck, damaged or incorrectly assembled

• | Fluid pump screen assembly plugged or damaged

• | Fluid pump rotor guide omitted or misassembled

• | Fluid pump rotor cracked or broken

• | Porosity in fluid pump

• | Fluid pump surfaces not flat

• | Excessive fluid pump rotor clearance

• | Pump slide seal out of location

• | Pump vanes damaged

• | Pump slide spring damaged

Pressure Control Solenoid | Damaged