Dot 3 0r Dot 5 brake fluid?
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From: So. Cal.
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Dot 3 0r Dot 5 brake fluid?
I know this is for vettes, but this is the only forum I belong to. My daughter has a 2003 mustang. Which brake fluid does it use? Thank you.
Le Mans Master
Joined: Aug 2005
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From: Merritt Island, FL
It should say on the filler cap of the brake master cylinder. DOT 3 or 4, most likely -- DOT 5 is silicone fluid, which should be considered race-only, and never used in a street car. The silicone fluid doesn't absorb water, which sounds nice on first impression, but it can lead to vapor pockets forming, which reduce the hydraulic efficiency of the system.
Instructor
Joined: Jul 2007
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From: Toronto(Don Mills) Ontario
It should say on the filler cap of the brake master cylinder. DOT 3 or 4, most likely -- DOT 5 is silicone fluid, which should be considered race-only, and never used in a street car. The silicone fluid doesn't absorb water, which sounds nice on first impression, but it can lead to vapor pockets forming, which reduce the hydraulic efficiency of the system.
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
DOT5 fluid is a silicone-based fluid and using it will cause cavitation in the ABS pump and that creates air bubbles. NEVER use DOT5 fluid in an ABS-equipped car 
Domestic cars use DOT3 brake fluid as the original fill. Some European cars will use a DOT4 fluid.
For street use, a good quality DOT3 fluid will work just fine. Castrol LMA, Valvoline, or even the Ford Motorsports HD fluid will do the job.
Domestic cars use DOT3 brake fluid as the original fill. Some European cars will use a DOT4 fluid.
For street use, a good quality DOT3 fluid will work just fine. Castrol LMA, Valvoline, or even the Ford Motorsports HD fluid will do the job.
Thread Starter
Corvette Enthusiast
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From: So. Cal.
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brake fluid
Thank you all!!! This forum is awesome!!
