Different Brake Fluid??
Thread Starter
Le Mans Master
Joined: Sep 2003
Posts: 6,386
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From: Just a little outside San Antonio, Texas
Different Brake Fluid??
Picked up some DOT 4 yesterday because I couldn't find any DOT 3. There wasn't even a place on the shelf for DOT 3.
Are DOT 3 and DOT 4 brake fluids interchangeable?
Are DOT 3 and DOT 4 brake fluids interchangeable?
Race Director
Joined: Jul 2004
Posts: 16,795
Likes: 62
From: Lake Havasu City, AZ
DOT 4 and DOT 3 are compatible. They are both glycol ether based. DOT 4 has a higher boiling point because it is borated.
BUT DOT 5 fluids are silicone based and NOT compatible with DOT 3 or DOT 4
BUT DOT 5 fluids are silicone based and NOT compatible with DOT 3 or DOT 4
Le Mans Master
Joined: Aug 2002
Posts: 8,222
Likes: 0
From: Norfolk VA
I've been using DOT 4 in the brakes and clutch for over 2 years now.The only thing about DOT 4 is that usually it needs to be replaced more often, if memory serves me correctly, DOT 4 should be flushed every year while DOT 3 can stay in the car for 2 years. Doesn't matter much to me though, longest brake fluid is in my car is about 4 months over the winter.
