4L60 (700-R4) Automatic Transmission

Fig. 1 Cross-Sectional View Of Turbo Hydra-Matic 4L60 (700-R4) Automatic Transmission:

The model 4L60 (700-R4) Fig. 1, is a fully automatic transmission consisting of a 3-element hydraulic torque converter with the addition of a converter clutch, Two planetary gear sets, five multiple disc type clutches, two roller or one-way clutches and a band are used to provide the friction elements which produce four forward speeds, the last of which is overdrive. A hydraulic system pressurized by a variable capacity vane type pump provides the pressure required for the operation of the friction elements and automatic controls. The gear ratio changes are fully automatic in relation to the vehicle speed and engine torque. Vehicle speed and engine torque are directed to the transmission providing the proper gear ratio for maximum efficiency and performance at all throttle openings.

Fig. 2 Lockup Torque Converter:

The torque converter hydraulically couples the engine power to the gear sets and provides additional torque multiplication whenever the converter clutch operates in the unlocked mode. The converter clutch, Fig. 2, allows converter drive and driven members to operate as one unit when applied, providing a mechanical coupling between the engine and transmission.