GM-51196 is a set of 2 tools that correctly install the solid Teflon seal on the stator shaft. GM-51196-2 is a 3.5" long, 1.9" OD smooth tube that covers the end of the stator shaft, protecting the seal from damage as it slides over the splines of the shaft. GM-51196-1 has expandable fingers that snug fit the protector and evenly push the seal down the protector into its groove on the shaft without over-expanding the seal. Previously essential GM-50912-1, developed for the 8L90, is used for compressing the seal. It has a tapered ID that gradually compresses the seal to the correct OD so it will fit inside the torque converter hub without being nicked or cut as the converter is installed.