Valve bore wear results in loss of apply oil, sluggish valve movement and sticking valves causing shift complaints and clutch distress.
Install the Sonnax oversized valve kit that fits in any of the three locations (3-4 and 4-5 shift valve, safety mode valve) after refurbishing the bore to eliminate bore wear and sticking valves.
A stuck or worn safety mode valve in the 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. Sonnax has developed an oversized valve and control valve kit that, when installed in a refurbished bore, restores the necessary hydraulic clearances required for proper valve function. This kit 55211-14K can be used in the 3-4 and 4-5 shift valve bores as well as the safety mode valve location.
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.
November 24, 2015
Topics: Vacuum Test Guides Vacuum Testing Transmission GM 5L50-E Transmission 5L40-E TransmissionRead Now
Contact a Sonnax Parts Distributor.
A vacuum test at ports indicated (Figure 1) fails to hold indicated minimum vacuum amount.