6T40 Transgo Shift Kit Valve Body Repair Gen1 2007-2012

Transgo SK 6T40-A shift kit for the Gen 1 GM 6T30, 6T40 and 6T45 six-speed transaxle, 2007 through 2012. This is the valve body repair that saves a worn casting: instead of reaming oversize bores, the kit drops in replacement valve trains sized to seal in the bores you already have.

Three circuits get rebuilt. The AFL (actuator feed limit) valve comes as a complete drop-in assembly with its own bushing, valve, spring, spacer and retainer, so the AFL function is restored inside the existing worn bore. The TCC regulator valve is a hardened steel valve with re-positioned longer lands and a scarf-cut sealing ring, which is what lets it hold pressure in a bore that has already egged out. The pressure regulator valve is likewise a new design with longer lands to bring line pressure control and boost response back. New O-rings and diaphragms are included to renew the TEHCM pressure switches while the valve body is apart.

Symptoms this addresses: erratic or hunting torque converter clutch, soft shifts or flare on the 1-2 and 2-3, burned friction plates from low apply pressure, and slow line pressure boost response. It covers the pressure-switch and pressure-control DTC family these units set - P0741, P0751, P0752, P0757, P0776, P0777, P0796, P0797, P0842, P0843, P0872, P0873, P0877, P0878, P0989, P0990, P2714, P2715, P2723 and P2724.

Gen 1 only. Confirm the build before ordering - the Gen 2 valve body uses a different casting and takes a different kit. Typical Gen 1 vehicles are 2008-2012 Chevrolet Malibu and Equinox, 2011-2012 Cruze, Buick LaCrosse and Regal, GMC Terrain and Saturn Vue.