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Copper contaminated brake fluid?

Recently had front brakes done on "05 Buick Lesabre. Garage said a test strip showed copper contamination in brake fluid, so I agreed to a fluid flush. 2 monthes later, oil change at same garage, they said brake fluid was contaminated with copper, wanted to flush it. Is this a real problem, or are they blowing smoke up my whatiz? What is the potential downside? Thanks to all who reply.


  • edited August 2009
    Is this a quick oil change place?

    When tests of brake fluid show a high level of copper, this indicates that the corrosion inhibitors in the fluid are depleted. It is very unlikely that the corrosion inhbitors would be depleted within 2 months. Two years, possibly. Two months--no.

    Frankly, I am skeptical of their claims.
  • edited August 2009
    Do you have copper or brass lines or fittings? If not, there is no way copper can get into the fluid - it isn't there.
  • edited August 2009
    Why would the shop pick copper to be the contaminate and not just water?
  • edited August 2009
    "Test Strip"??? Copper??? Sounds like complete BS.
  • edited August 2009
    The brake caliper to hose uses copper sealing washers. A brake fluid flush is good but it sounds like their pitch is full of pitch.
  • edited August 2009

    As I said previously, it is virtually impossible for copper levels to reach a high level in brake fluid within 2 months, but regarding the topic of brake fluid and copper:

    "The Automotive Maintenance and Repair Association (AMRA) has
    issued a Uniform Maintenance Service Recommendation for
    changing brake fluid when its copper content reaches 200 ppm.
    This recommendation was issued by the AMRA in April 2004, and
    is based on extensive testing determining copper content to be a
    predictor of brake system corrosion. As the corrosion inhibitors in
    brake fluid deplete over time, copper components in the brake
    system are among the first to corrode, with copper levels rising in
    the brake fluid as a result. Copper corrosion is closely followed by
    corrosion of iron based components, indicated when copper levels
    in the 150-200 ppm are reached. To provide maximum brake
    component life, corrosion in the brake system must be minimized
    by periodic brake fluid changes. Such fluid changes maintain
    proper levels of corrosion inhibitors in the fluid and also minimize
    water content."
  • edited August 2009
    This is who the AMRA is:

    Dave Baier
    Monro Muffler and Brake

    Vice Chairman
    Richard Schossler
    Goodyear Tire & Rubber Company

    Secretary/ Treasurer
    Stuart Manning
    Just Brakes

    Immediate Past Chair (Ex-Officio)
    Jack Fischbein
    Jiffy Lube International
    Chuck Abbott

    Denny Bowen
    Hunter Engineering Company

    Mark Christiaanse
    Tenneco Automotive

    Joe Henmueller
    Midas International

    Ricky Jackson
    Jiffy Lube International

    Alex Kolosiwsky

    Jack MacDonald
    Pep Boys

    Len Vogt

    I don't see one car manufacturer in the group.
  • edited August 2009

    ...and some car manufacturers still don't list brake fluid changes anywhere in their maintenance schedule, despite the fact that brake fluid is hygroscopic and does deteriorate over time. As we all know, car manufacturers like to make their products appear to be as maintenance-free as possible, and are beginning to delete references to transmission fluid changes in addition to the fact that they may have never listed brake fluid changes in their maintenance schedule.

    Just because you and I would not necesarily want to patronize any of the firms that you listed above, does not preclude that it is just good practice to do a brake fluid change every 3 years or so. And, if the presence of copper in the fluid is a valid early warning of the need to change brake fluid, that might be a good thing to know.

    However, as I said previously, if the OP had his brake fluid changed 2 months ago, then someone is just trying to blow smoke up his butt with the recommendation to change the fluid again.
  • edited August 2009
    I suspect the "Test Strip" ALWAYS reveals the need for a brake fluid flush..
  • edited August 2009
    I got the fancy treatment, the guy shoved an electronic gizmo into my brake fluid, came out with a red LED flashing, told me I needed a flush. I told him I'd do it (I did), he obviously didn't like that answer. I open my hood a day later, there's the brake reservoir cap sitting on the inner fender! I got the last laugh - he left the gizmo there, too.

    I also am worried about a group that makes money selling (often unneeded) maintenance coming up with these dire predictions. I would believe it if it came from a brake manufacturers association. Not them.
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