The STL-8L90 "Shudder" Solution valve body upgrade from TransLab Engineered by Superior Transmission parts is the solution to eliminate shudder or shaking caused by a valve in the 8L valve bodies. This fix also alleviates valve body breakage. Works In previously Reamed OR Stock SL Dampeners Bores. USE PART # STL028 for a Precise and Correct Flt every time. Designed speclflcally to work as a complete replacement for previously Installed and then failed dampeners ... whether initially the valve body has been reamed or not.