davids2toys Dave if the trans was rebuilt and all new parts in it, I would just run a normal run of the mill gear lube through the trans for about 300 miles. This will wash out any metal partials and help breakin the syncro's of the trans. After this is choice. If you are just street driving and cruising, any semi syn
oil will be fine. If you are going racing that another story and would run a different
oil. 75/90w gear lube will work fine. Racing trans will run a lighter fluid like autotrans mission stuff. Looking for less drag and quicker shifting. Don't get crazy. I race and run 75/90 valvoline and change it every year. Check for metal on the drain plug, and install new fluid. The color is fine after 10-15 events. Biggest pain is installing the new fluid, need a pump or remove the tunnel of the car to fill. Rick L. Ps Dave I think the stuff you are looking for is old school of about 30 years ago. Try Dave Kee who rebuilds Toploader trannies.