Well then make a t chart and weigh the positives and negatives bra.

I've done that, was basically just seeing if anyone has had prior experience with the t56 as this is my first car with any kind of horsepower.

Redline >

Decided on the GM synchromesh

Good choice

this is what we use, never had an issue

although our trannys are "manual" they are just high/low

Also very good choice.. Redline is always rated in the top tier of lubricants

redline imo

the "shock" we put on the trannys is the reason we use it, that and the sustained high rpms, to keep the shit from burning

Gm syncromesh followed by pennzoil synchromesh is smoothest in a stock trans. If it has been rebuilt it will depend on how the clearances were set. Mine will grind going into 4th when its cold with the thicker synchromesh. Tick performance recommends a good ATF +4 in their built transmissions. Seems backwards but the clearances are set tighter so a thinner weight fluid is required. Being rebuilt with carbon fiber blocker rings allows the use of the more exotic synthetics but they claim any old atf will work. Overfill it a half qt. Some people suggest a full quart over but there is some evidence that too much will cause heat dissipation issues.