Did some research on the oils and leaves some questions about materials used in the tranny.
Lucas is a GL-5 hypoid gear oil and not designed for transmissions using brass/bronze synchronizers. You will need a GL-4 oil, such as Red Line 50305 MT-90 75W90 if it uses Brass/Bronze synchronizers..
So it seems that it would be dependent on the type of metal used for the synchronizers. Will need to check on this.
