September 30, 2005
In Aisin AW 55-50SN and 55-51SN units, the original equipment lockup control valve sleeve is prone to significant wear due to constant oscillation of the plunger valve, resulting a multitude of converter complaints. Converter feed pressure from the secondary pressure regulator valve is directed in part to this plunger valve assembly and becomes converter apply pressure. The plunger valve aids in correctly positioning the inboard lock up control valve to regulate converter apply. If this sleeve is worn, converter apply pressure is reduced and the converter may not fully apply. Sonnax lockup control valve kit 59947-03K restores proper hydraulic clearances and prevents valuable converter apply pressure loss.
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.