For 1990-2009 cars

Check | Causes
--- | ---
DEFINITION: A large engine RPM increase and forward vehicle speed decrease do not immediately occur when the transmission is shifted from overdrive or fourth gear in Drive or manual third range to either first, second gear, or third gear, manual second.
Coast Clutch |

• | Damaged or cut piston

• | Damaged or worn clutch plates

• | Damaged or stuck ball check valve

Overdrive Clutch |

• | Damaged or cut piston

• | Damaged or worn clutch plates