[kavadarci]

2009 e90 LCI.
Brake fluid was flushed at 66.000km
Bmw SA tells me it's due for another brake fluid flush.

I have never done brake fluid flush on any of my previous cars. Is it really needed to change the brake fluid that often? Visually the fluid is clear and clean.

Thank you.

[obert]

If its free why not let them, they go off of what ever the car is telling them that needs to be changed

Its probably over kill to change the brake fluid that often

[Brad from the OC]

Originally Posted by kavadarci

2009 e90 LCI.
Brake fluid was flushed at 66.000km
Bmw SA tells me it's due for another brake fluid flush.

I have never done brake fluid flush on any of my previous cars. Is it really needed to change the brake fluid that often? Visually the fluid is clear and clean.

Thank you.

Brake fluid contains glycol which sucks moisture from the air. Over time, the brake fluid water content increases which reduces the boiling point. Under hard braking conditions, old brake fluid can reach the boiling point and can cause brake failure or brake performance reduction. You can not tell visually if the brake fluid has reached a lower boiling point. I'm sure BMW suggests a once every two year brake fluid change as that is probably the point where braking performance is reduced, so by changing the fluid you are restoring the designed boiling point.

[Clifton]

Fluid really should be flushed annually, but under BMW "free" program it is every two years. You should definitely replace, regardless of the fluid's appearance.

Adding to what others have mentioned about the performance benefit, changing the fluid also helps add life to the internals and rubber seals of the brake system.

[kavadarci]

Very good. thank you for the input. will replace

[ejj]

I think this is a German thing! We had a VW that recommended changing the brake fluid annually. Every other car I've owned (Japanese, American) has recommended changing the fluid every 50k miles at most.

That being said, I usual flush the while system when I change all the brake pads....

[kavadarci]

Forgot to ask, since it is not under warranty and I will be replacing the fluid what is the best fluid to use. Thank you.

[Clifton]

Originally Posted by kavadarci

Forgot to ask, since it is not under warranty and I will be replacing the fluid what is the best fluid to use. Thank you.

ATE Typ 200. Stick with the amber and not the super blue. The super blue will dye your reservoir blue.