November 24, 2015
Required tool kit F-55211-TL14 is no longer in production. Check with your distributor for availability.
A stuck or worn safety mode valve in GM 5L40-E, 5L50-E can result in the L/R clutch staying applied on a 1-2 upshift, causing a 1-2 bind-up condition. Wear at the 3-4 or 4-5 shift control valves allows signal and apply oil pressure to exhaust, preventing proper valve movement that causes flares, shift complaints and clutch distress. Reconditioning the bore and installing Sonnax oversized 3-4, 4-5 and safety mode valve kit 55211-14K restores the necessary hydraulic clearances required for proper valve function.
This kit can be used in any of three locations. If using in the safety mode valve location, the control (small) valve is not used.
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.