[wrp]

[QUOTE=oaklandish;25203678]Well, looks like any old DOT 4 or this Castrol BMW brake fluid should work for our X3. I’m way late on mine.

I think you really need DOT 4 LV (Low Viscosity) not just plain DOT 4.

[doru]

Originally Posted by RL325xi

Off subject, What kind of brake fluid should 2012 35i use ?

For the last 20 years or so I use only ATE brake fluid for my BMW's.
If you want to be 100% sure you use the correct brake fluid, here are 2 options:
ATE TYP 200 brake fluid DOT4 - boiling point 280°C or 536°F (dry) and 200°C or 392°F (wet)
Pentosin Super DOT4 - boiling point 265°C or 509°F (dry) and 165°C or 329°F (wet)

There might be other DOT4 brake fluids available as well, but use the one that has the highest boiling point. Brake fluid is hygroscopic, so once it gets tainted (and it will), the boiling point stays still relative high, so you won't risk losing brakes.
Once it's water absorption reaches 5% or so, you have to flush it. The humidity in the fluid can adversely affect metallic components inside your braking system. Think of ABS.