As an ex M3W owner I assumed the grease found in new BB's was put in for break-in purposes. Certainly there was no mention of using any form grease in the service section of handbook. Since the crown wheel and pinion are in a bath of transmission oil there are no advantages to be gained from the stiction of grease since lubrication will be near instant. Heat dissipation will also be superior with oil compared with any form of grease.

Having said this the Burman gearbox on a Vincent I once owned specified mixture of grease and EP90. I assumed the former was to assist in smoother gear selection. The large series Land Rover front swivels also benefit from semi-liquid grease when seals are a little worn, but that's for lube retension when the EP90 drips out a little too freely.


Richard

2018 Roadster 3.7
1966 Land Rover S2a 88
2024 Royal Enfield Guerrilla 450
1945 Guzzi Airone