What is the difference between PWM and non-PWM torque converter clutches?
PWM stands for “pulse width modulation”. In transmission control applications, PWM is a way of controlling a solenoid so that it applies varying amounts of hydraulic pressure according to computer control. PWM torque converter clutch systems use apply and release the clutch gradually to improve shift feel. Unfortunately, many of the PWM controlled systems cause the clutch to slip, and over time, eventually fail. Over time, manufacturers have introduced and then later removed this gradual apply / gradual release feature. Some types of transmissions have been built with both PWM and non-PWM versions of the converter clutch. For those transmissions, COMPUSHIFT has a setup menu selection that lets you choose PWM or non-PWM. Whether PWM or not, COMPUSHIFT always does a quick apply and release of the torque converter clutch. We feel that it is more important, especially in high-horsepower applications, to preserve the life of the clutch rather than improve shift feel.
