What Are You Doing To/With Your Car Today?

At the risk of sounding ignorant why DOT 5? Is it that much better or does your set up have to have it? Very interested in advantages. I have to re-do my brakes, lines and all.
Ignorance, mostly. Higher number is better? :rolleyes:

What I've actually picked up somewhere is that DOT-5 is silicon based and doesn't absorb water. And that it won't strip the paint off my calipers. Not sure how much of that is true, though. But it is silicon-based.