Hello I bought a 1959 TR3a. I'm nut shure about the gearbox in it. A TR3 Gearbox needs SAE 30 oil. A TR4 gearbox needs SAE 90 oil. Does anybody knows from what number of gearbox SAE 90 is needed. I all ready drained it, so I don't know if its a synchronised first or not. Greetings from Belgium Guido