dot 4 synthetic brake fluid question
07-27-2015, 01:21 PM
#1
Melting Slicks
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dot 4 synthetic brake fluid question
I purchased this castrol dot 4 brake fluid and was wondering if it's compatible with dot 3?
Just noticed "synthetic brake fluid" at the top of the label.
07-27-2015, 01:32 PM
#3
Melting Slicks
07-27-2015, 01:34 PM
#4
Burning Brakes
Generally, DOT 3 and 4 can be used interchangeably. I always used that Castrol DOT 4 in my older cars, and it worked fine. It should say on the back of the bottle that it's okay to use with DOT 3, mix it. What you CANNOT mix is DOT 5, which is silicone based fluid. Putting DOT 5 silicone in with DOT 3 or 4 will lead to problems. But DOT 3 and 4 get along fine together.
