Jump to content

Gear Oil clarify?


Recommended Posts

06 RT

75w90 Syn. OK for tranny AND final drive?


Also, which panels, screws should be removed for TB synch?

Link to comment

I don't know for sure. The Castrol SAF-XO is identified specifically as a final drive lubricant. It is a synthetic 75/90W lubricant which BMW specifies for standard differentials. There is also a Castrol SAF-XJ which is a synthetic 75/130w or 75/140w that BMW specifies for limited slip differentials. I don't think that the final drive is an extreme environment and probably any good gear oil will work. I don't know if there is an advantage to the heavy rating. I wonder if the lighter rating might help in the efficient transfer of energy and result in slightly better mileage? When I drained mine I noticed that it was black with a metallic sheen. I have seen black moly additives in oil before. I have not heard of moly being added to synthetics, so, I have no idea if there is anything special about the specified SAF-XO other than it is hard to find and expensive.

Link to comment


This topic is now archived and is closed to further replies.

  • Create New...