Reviewing the service schedule I see no mention of a brake fluid flush. I called my nearest dealer and they said it is a closed system and therefore it does not get contaminated and would never need a flush. In normal cases is this actually true? What about condensation?

The dealership said that if some shop tells me I need a brake flush then they either no nothing about my car, or they are trying to rip me off. Can anyone else confirm this to be true?

 

At my dealership, the service guy pointed out how black the fluid had become and I went ahead with flush. In the past, I have trusted this guy. But probably without good reason.

 

I can't see the harm in just getting it done. Maybe it is just an "as needed" thing and not so much an "interval" thing. Thanks for sharing your experience.

 

There are differing schools of thought on this and it depends somewhat on your geographic locale (i.e. more humid areas tend to cause more moisture absorption), but I've always heard that it's not a totally closed system and the brake lines do absorb some moisture over time, especially with DOT 3 fluid that is stock with our cars. Take a look at your BMC reservoir after a year - it usually looks a bit darker than when it started, indicating that moisture/contaminants find a way in - through seals, lines, etc. DOT 3 Brake fluid is hygroscopic, meaning it absorbs water over time and with hard brake use, and the absorbed moisture lowers the boiling point of the fluid, which makes it even less effective.

I typically flush my brakes every 2 years and it really firms up the brake pedal. I suppose the same could be done with just a brake bleed, but most dealers have power brake bleeders which essentially flush the fluid anyway.

 

Thanks man! That all sounds logical to me. I think I will start flushing it on a similar interval. It can't hurt.