The 1993 4L80E transmission uses a TV cable to control the transmission's shift points. The TV cable is connected to the throttle body and as the throttle is opened, the TV cable pulls on a lever on the transmission which increases the hydraulic pressure to the transmission, causing it to shift at higher RPMs.
The 1995 4L80E transmission does not use a TV cable. Instead, it uses an electronic throttle control system (ETC) to control the transmission's shift points. The ETC system uses a sensor to monitor the throttle position and sends a signal to the transmission's electronic control unit (ECU). The ECU then adjusts the transmission's hydraulic pressure to shift at the appropriate RPMs.
2. Governor
The 1993 4L80E transmission uses a mechanical governor to control the transmission's shift points. The governor is connected to the transmission's output shaft and as the output shaft speed increases, the governor weights fly out and cause a valve to open which increases the hydraulic pressure to the transmission, causing it to shift at higher RPMs.
The 1995 4L80E transmission uses an electronic governor to control the transmission's shift points. The electronic governor uses a sensor to monitor the output shaft speed and sends a signal to the transmission's ECU. The ECU then adjusts the transmission's hydraulic pressure to shift at the appropriate RPMs.
3. Shift Solenoids
The 1993 4L80E transmission uses two shift solenoids to control the transmission's shifts. The first shift solenoid is called the "1-2 shift solenoid" and it controls the shift from first to second gear. The second shift solenoid is called the "2-3 shift solenoid" and it controls the shift from second to third gear.
The 1995 4L80E transmission uses three shift solenoids to control the transmission's shifts. The first shift solenoid is called the "1-2 shift solenoid" and it controls the shift from first to second gear. The second shift solenoid is called the "2-3 shift solenoid" and it controls the shift from second to third gear. The third shift solenoid is called the "3-4 shift solenoid" and it controls the shift from third to fourth gear.
4. Electronic Control Unit (ECU)
The 1993 4L80E transmission does not have an ECU. The transmission's shift points are controlled by the mechanical governor and the TV cable.
The 1995 4L80E transmission has an ECU. The ECU receives signals from the electronic throttle control (ETC) system, the electronic governor, and the shift solenoids. The ECU then uses these signals to control the transmission's hydraulic pressure and shift points.
