Copper in brake fluid

Not open for further replies.
Nov 26, 2007
Duluth, MN
Today I went in to get my tires rotated and balanced at Firestone for free as part of buying and having them installed there. Of course, they are looking for anything else to repair, which I don't mind, but usually pass on any extra services offered.

This time, the manager came back saying the tech had found lots of copper in my brake fluid and that a brake system flush would be appropriate. I'm curious if this is a real problem or not and where the copper comes from. Also, is there a way to check the copper levels in a fluid in under 60 seconds or do they usually just say that? Thanks.

This is a good indicator that certain degree of contamination in your brake fluid.

Why copper? copper brazing has been applied to various different parts of the hydraulic braking system (various joints,etc.) and as the fluid becomes contaminated by moisture, etc. the usual end result would be elevated copper readings. Instead of the good ole fashion of testing the moisture level/content in brake fluid, these days, some mechanics resort to using test strips for copper in brake fluid.

It is a valid/legit means of testing your brake fluid. I would change it and perform a flush and fill if it doesn't cost to much.

Thanks for the information. For better or worse I find myself heading down the road of DIY brake fluid flush...a new topic on such will probably come up soon!

Not open for further replies.