Flush brakes?
I never have, though I know it's the right thing to do.

But in my defense...if the idea is to remove the water droplets to avoid corrosion, how can you do that through the bleeder which is at the high point in the caliper? Water is denser than brake fluid and it therefore settles to the bottom of the piston bore in the caliper which is the furthest from the bleeder valve. So how does flushing the brake fluid off the top remove the water that is on the bottom?

Kind of a serious question.

The 'synthetic' DOT4 is made with silicone, do not use it with regular DOT4:



If you do decide to convert to silicone fluid, it should be done as part of a total brake system overhaul, with freshly rebuilt or new calipers, wheel cylinders and master cylinder. Silicone fluid should not be added to a system that contains even small amounts of glycol fluid or contaminants. Merely bleeding the system is not enough, as there will be pockets of old fluid and sludge that will not bleed out. Silicone fluid tends to concentrate any residual glycol fluid, moisture and sludge into slugs instead of allowing their dispersal throughout the fluid, as does glycol fluid. This can lead to relatively severe but localized problems, rather than the more general system deterioration experienced with old moisture-laden glycol fluids. This may be a factor in reports of leakage when silicone fluid is used in non-rebuilt systems that had been operated with glycol fluid. A "new" system full of silicone fluid will require very little maintenance for years.

Again, don't mix the two. Only bad results can occur from this.
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My back feels better when I sit in a Volvo seat

Synthetic? is it made from reconstituted catfish whiskers?
Whatever it's made of the company has your welfare foremost in mind?

Wally World has Prestone DOT 4, probably cheaper.

Crabby