Vehicles equipped with Aisin AW 55-50SN and 55-51SN transmissions may suffer from delayed Forward engagement and require increased throttle for engagement. These problems are caused by bore wear at the neutral relay valve, resulting in loss of clutch engagement pressure. This can be fixed with the Sonnax oversized neutral relay valve kit 59947-35K. The Sonnax valve kit restores clutch pressure, which will eliminate delayed engagement and the need for increased throttle.
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.