In Ford Gen. 1 and 2 6F35 transmissions, the function of the solenoid pressure regulator is to provide regulated pressure to shift solenoids. Wear in the solenoid pressure regulator bore causes low clutch pressure and results in transmission slips and harsh shifts. This eventually leads to a loss of 4th through 6th Gears and finally the loss of transmission function.
Installing Sonnax solenoid pressure regulator valve kit 144740-37K 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.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.
Note: Due to the design changes on the Sonnax sleeve and valve, post-install vacuum testing at the inboard port is not a valid sealing test.