Hello folks. I would like to create a clear DIY guide for the community for changing the Differential Fluid since i could not find one for the F85/86 but the info is limited.
I would like to cooperate with other members so it can be a sticky DIY guide for us.
I recently had a tire valve leak and had to drop the car to the dealer since i was in a roadtrip and i forgot my lock nut at home. Also let them change the engine oil while it was getting fixed (FCP Euro Kit also sitting at home) . I gotta phone call from the advisor saying that your differential fluid also due would you like us to replace as well on my 32K miles f85?
I was like i did not know 4 years or 32K miles makes my differential oil due but i said i will skip this time. So i finally arrived home and made some research about it. As usual all different viscosity options popped up.
realoem says
75W-85 or
75W-90 recommended but in the mean time
75W-140 also listed one of our recommended oil on ECS.
Since i live in Florida, OEM 75W-140 feels like a great choice since i also use this on my E93 M3.
But then i came across someone saying that F85 differential has inner and outer part. The outside chambers use 75w140 and center section uses 75w90. I have no clue about this because i thought we have only one refill and one drain plug. Can someone clarify this?
Also realoem shows 3 Hex Bolt with washer listed on our differential.
2xM12X1,5 and 1xM14X108 . If there is 3 plug on this axle drive , 2 of them refill and one of them for drain?
If you guys know anything about it please share, so i will make a DIY guide with gathering all the info thru this topic.
Thank you!