The "blue tag" ZF6 transmission was introduced mid year 1993 and was the manual transmission option for Corvettes until the end of the C4 generation in 1996. From 1989 to mid-'93, the "black tag" ZF6 filled this role. The main transmission page of this site details the swap of a black tag ZF6 into my Monte SS. This transmission had an unknown history, as it was bought used. There is some gear chatter at idle, and some gear noise under load at 1800-2100 RPM, as well as below 1400 RPM in higher gears. I thought that this was due to the transmission being possibly old and worn out, so when the opportunity presented itself to purchase an NOS (New Old Stock) ZF6 for $1200, I jumped on it. This transmission is the later blue tag trans, and this page outlines the lessons learned during the install of this trans. The basic procedure is the same as the previously outlined black tag.