4L6-ISO-3 - 4L60E, 4L65E, 4L70E and 4L75E Valve Kit TCC Upgrade for SRTA Rebuild Valve Bodies 1993-2011 Except Hybrid units Oversize TCC Lock Up Isolator valves (3) : For GM/SRTA (GM Service Replacement Transmission Assembly) transmission and GM Rebuilt Valve Bodies. Has patented isolator valve that is longer, oversize, and self cleaning. Valve reduces tilting and future wear. Drop in no Boring! Does not require transmission removal for proper installation