IMHO Three years is way too long - I do it at least once a year. Even a well sealed brake system will absorb significant amounts a moisture leading to deterioration of brake lines and components from the inside (totally avoidable). Bleeding brakes is a job made much simpler by the installation of "Speed-Bleeders" - bleeding fittings (screws?) with integral one way check valves - in place of the stock caliper and wheel cylinder fittings. I also have a special brake fluid bottle cap that allows me to set a quart bottle of brake fluid upside-down on the reservoir - automatically keeping the level full.
With these simple tools and some experience you can one man bleed your brake system very rapidly and easily. I can do my Explorer in about 15 minutes. My cars take longer since I have to remove wheels to get to the fittings - but no more than an hour using a floor jack.
When you bleed your system, compare your three year old fluid with fresh fluid - if you are a true car enthusiast you will never let it go that long again!
99 Tropic Green SVT, Tan Leather, 20K miles, "Nice Twin" (factory stock).
99 Tropic Green SVT, Tan Leather, 28K miles, "Evil Twin" (Turbo AER 3L and more in progress)
96 Red LX, Opal Grey Leather 2.5L, ATX, 22K miles
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