[kadhimmu783]

Got 4x4 and brake lights on the dashboard.

4x4 works most of the time, but somedays it stops working and started to get this grinding noise. As you can hear in the youtube video at

I read different post and a lot of people change the "transfer case actuator motor" or some just change the " transfer case worm gear".

But not sure if I should change the actuator motor yet or just try changing the transfer case fluid as 4x4 is still working.

Not sure if it has anything to do with anything but its been quite cold lately ~ -10 to -20 degrees Celsius.

Thanks in advance!

[hassmaschine]

first thing to do would be to change the fluid and reset adaptations. Does it do it in a straight line or only while turning?

[kadhimmu783]

It does it in a straight line. Drove for an hour today and 4x4 was working the hole time, noise was very minimal. Only notice sometimes.
I will try changing the fluid and see how that goes. Do you know if I have to get the fluid from the dealership? Or can I buy it somewhere else like Amazon?

[hassmaschine]

you need the specific fluid, I don't know if Amazon sells it but it has friction modifiers in it that allow the clutches to work properly.

[kadhimmu783]

Yah, I will just get it from the dealer.

Thanks

[PhaseP]

https://www.fcpeuro.com/products/bmw...ll-83222409710

I have this one in mine for at least a year.