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 S89741CA restores proper hydraulic clearances and prevents valuable converter apply pressure loss. Sleeve is manufactured from highly wear-resistant billet aluminum; Hardcoat anodized aluminum valve combats premature wear; Drop-in Zip Valve™ parts install quickly and easily
Valve and Sleeve; Lock-Up Control
