GM 6L45, 6L50, 6L80 and 6L90 units often suffer from shift
abnormalities caused by excess wear in the actuator feed limit (AFL)
bore. This wear prevents proper regulation of oil pressure supplied to
control solenoids resulting in harsh or soft shifts, solenoid codes,
wrong gear starts, and clutch/band failure. Installing Sonnax actuator
feed limit valve kit 104740-47K renews the hydraulic integrity of this
circuit, restoring normal shift operation and feel. This drop-in,
sleeve/valve assembly provides a new and unworn bore for hydraulic
sealing of the valve while the sleeve seals off existing moderate bore
wear to prevent fluid loss. A new spring to provide correct limit
pressure with the sleeve/valve assembly is also provided.
Proper AFL action depends on correct line pressure supply to the AFL
valve. If problems are found with line pressure, Sonnax offers oversized
pressure regulator and boost valve kit 104520-07K.