Brake fluid
Thread Starter
Instructor
Joined: Nov 2008
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From: Erie CO
Brake fluid
I went to change out the brake fluid in the reservoir and see the brake fluid is a green color. I was going to put in prestone 3 brake fluid which is clear. Why is the old fluid green and will mixing them create a problem.
Le Mans Master
Joined: Mar 2004
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From: Ft. Lauderdale Fl
Could it be.....not your brake fluid but your coolant?
Last edited by runner140*; Apr 20, 2011 at 10:50 AM. Reason: add
Team Owner
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The only time mixing becomes a real problem is when you combine glycol and silicone based fluids. It's unlikely, but make sure someone hasn't dumped DOT 5 in your brakes. Suck a little out of the reservoir then drop a bit of water into it. If the water goes into solution, then you're fine with any DOT 3,4. If not, then go find some DOT 5.
Thread Starter
Instructor
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From: Erie CO
Former Vendor
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St. Jude Donor '11-'12-'13
I'm not aware of any fluid manufacturers using green - but discoloration is typical over time. Most fluid are amber colored or clear, some like ATE (which wcsinx must have had) are blue or gold.
It doesn't really matter why it's greenish just that it's DOT 3/4 - as mentioned above the only issue would be mixing silicone fluid with a glycol based DOR 3/4 or 5.1 fluid.
A quality DOT 3 will work fine and be the most forgiving (longest service period). DOT 4 is better if you're planning on some track days but wet boiling point will drop off quicker than a DOT 3 - and silicone should be avoided all together.
HTH
It doesn't really matter why it's greenish just that it's DOT 3/4 - as mentioned above the only issue would be mixing silicone fluid with a glycol based DOR 3/4 or 5.1 fluid.
A quality DOT 3 will work fine and be the most forgiving (longest service period). DOT 4 is better if you're planning on some track days but wet boiling point will drop off quicker than a DOT 3 - and silicone should be avoided all together.
HTH
Team Owner
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From: Western NY
From what I understand, brake fluids are tinted so you know when you've evacuated all of the "old" fluid when you're doing a complete flush. IIRC, the brand Motul fluid comes in different colors for that reason.
