What fluid for a 4-speed trans?

What Viscosity or Weight is the Synchromesh?

At 100°C, claimed viscosity is 9.08 cSt, which puts it solidly in the range for an SAE 80W gear oil. At 40°C, viscosity is 41.6 cSt, equivalent to an SAE 75W gear oil. So, calling it a 75W-80W would be accurate.

Synchromesh1.png Synchromesh2.png 5795.gif