Have you replaced yours with in the last 60k? If not its a good idea. You won't not know it's bad till it's too late! It's always better to catch a potential problem in the garage than on the road!
This is the specific fluid that is used in the X3 models using BMWs xDrive all wheel drive system. Labeled as BMW as
"Non-Lifetime" fluid.
Click HERE for more information.

As always please let me know if you have any questions! Feel free to shoot me a PM or email.
Cheers,
ECS Tuning