February 21, 2013
In Ford 5R55S and 5R55W units, Reverse pressure from the manual valve is routed through the Reverse engagement valve prior to applying the direct clutch. Excessive wear at the valve bore can prevent solenoid feed oil pressure from correctly positioning the engagement valve, allowing reverse pressure to be reduced. Low Reverse pressure can result in slipping or loss of Reverse, burned direct clutches or delayed Reverse engagement.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.