700R4 4L60 2004R TRANSMISSION Reverse Boost Valve & Sleeve Sonnax K77898

img{max-width:100%} 4L60 700R4 2004R Sonnax Reverse Boost Valve .283" for GM vehicles Kit Includes: 1 Boost Valve 1 Boost Sleeve 2 O-Rings Description: Vehicles with a 4L60 transmission often have problems with poor reverse boost or upshifts in manual low. These are generally caused by a worn reverse boost valve sleeve or wear at the pump body. Due to the differences in the thermal expansion rate of steel and aluminum when the transmission approaches operating temperature, the sleeve has been allowed excessive clearance and scrubs the bore. Features: Sleeve and valve are made from hardened steel for increased wear resistance O-rings added to the boost sleeve seal the reverse boost circuit and prevent leakage from the pump body bore Sleeve lands have been lengthened to add better sealing and stabilizing capabilities to prevent bore wear The reverse boost valve spool lands have been lengthened to aid in maintaining hydraulic integrity  We build all our torque converters. We