After reading Mr. Fixit's experience with getting so many hours on the Toyota brakes, I am curious as to how often Toyota recommends at least pulling the wheels and checking the shoes, and removing the wheel cylinders and checking condition of seals, bores, piston clearance. How often do you replace wheel cylinders or rebuild with new seals/pistons? Pistons can wear and you can get good seal when supplying brake pressure, and then when the pedal is released you get leaking.