February 21, 2013
Some common complaints associated with Ford 5R55W and 5R55S transmissions are high TCC slip RPMs under increasing loads, slip codes, and converter apply or release concerns. These complaints are often caused by wear at the I.D. of the TCC modulator plunger valve sleeve, due to constant oscillation by the pulse width modulated TCC solenoid. This plunger valve positions the TCC modulator valve, which feeds line to the apply circuit, which controls slip rate. Wear of the sleeve will allow the TCC slip rate to continue to rise, and could prevent full lockup.
Sonnax TCC modulator plunger valve kit 56947J-01K restores hydraulic integrity to the TCC solenoid circuit with precisely toleranced parts. The elevated modulated pressure will not raise apply pressure to the point of TCC piston fatigue, and will result in firmer TCC apply and reduced slip RPM in heavier use applications.
The valve bore inward of this TCC modulator sleeve wears rapidly. Always inspect for bore wear at the largest spool of the inner valve.
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.