Ford vehicles equipped with 5R55W and 5R55S transmissions often exhibit driveability concerns such as delayed engagement, harsh or soft shifting and erratic line pressure, often resulting in burnt clutches. These troubles may be accompanied by an erratic buzz and/or pressure control codes. A worn pressure regulator valve allowing critical pressure loss from the line pressure circuit is very often the cause of these problems. Installing Sonnax pressure regulator valve 56947J-77 eliminates pressure escape to restore normal line pressure control in all ranges.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.