Not Ranked
The absorption of water would cause rust. What I learned while installing my electric power brakes.
DOT 3 & 4 are Glycol based. They are used in production cars due to their ability to carry out contaminants within the braking system. These fluids attract moisture, so any moisture that would enter the system would be carried through and flushed out or diluted enough to not matter. Once you open a bottle of DOT 3 or 4 and sit it on the shelf, it starts to become contaminated, and if left long enough, cannot be used. This is why when bleeding your brakes with DOT 3 or 4, the fluid that comes out must be disposed of. BTW - It will eat the powder coating off the frame and will eat through the ceramic coating on your headers, I know this from experience unfortunately.
DOT 5 - silicone based. Does not carry contaminates through your system. Should be flushed through periodically with de-natured alcohol. Suggested by my electric power brake vendor to be used in my system. Higher boiling point was also a reason for me to install since my brake lines are so close to me headers.
Google DOT 3,4, and 5 - there is a wealth of info out there.
HTH,
Tim
|