In Aisin AW 55-50SN and 55-51SN units, the original equipment solenoid relay plunger valve sleeve is prone to wear due to the continuous oscillation of the plunger valve. Solenoid modulator pressure feeds into this sleeve, which then works to correctly position the inboard solenoid relay valve. This valve is responsible for directing lockup control fluid into the TCC signal circuit to apply the converter clutch, as well as directing B5 control fluid to the U1 shift valve to apply the 1-2 Reverse (B5) clutch. A worn sleeve will then prevent proper lockup control and B5 clutch operation, resulting in the noted symptoms. Sonnax solenoid relay valve kit S89741Q eliminates wear and restores proper circuit control. 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; Solenoid Relay
