We have a DP50 which is the same as the Nissan F04G45UT's we have. There has been a modification done to the later models that has grease nipples and a re-designed bottom bearing plate. In the early models we take the bottom plug out and grease it through that, then replace the plug. In the later models the seals are also fitted different in order to keep the dirt out. The new bottom plates are different and are not retro-fitted to the older models. Probably worth turning the seals over we have not done this yet (but will on the next rebuild) if the axle is greased regularily in the older type.