In the fleet that I serviced when I changed the Transmission fluid. The red Was/is TYPE F You can add the same. no sub. now if you drain it out to change it I would Replace it With a Low viscosity, that I purchased an NAPA, I took the empty John Deere Jug in the crossed referanced it to one they carry. In 20 years 13 tractors Only one trans problem, and it was not related to the lube. Some will dissagree what I print are only my Facts based on my 72 years of experiance, Some of the 318 have in excess of 4000 hours on the clock , NO rebuilds.. Life is good.. so is the 318;