Abstract: A method for controlling a torque converter clutch in an automatic transmission of a vehicle that includes an engine, an accelerator pedal and wheels, the converter clutch alternately connecting and disconnecting the engine and transmission when the clutch is engaged and disengaged. The method includes determining that the vehicle is either ascending a grade or operating in a loaded condition, determining that the clutch is engaged, determining whether the vehicle is operating in a curve, preventing disengagement of the clutch if the vehicle is either ascending a grade or operating in a loaded condition and the vehicle is operating in a curve, and allowing disengagement of the clutch if the vehicle is neither ascending a grade nor operating in a loaded condition.