when is the last time you changed your brake fluid? it must be changed every 2 years, regardless of miles driven. the only time i've seen seized calipers is on severely neglected cars that haven't changed their brake fluid in many years. brake fluid absorbs water from the air, and rots the entire system from the inside out, deteriorating all the seals, and corroding the insides of the calipers until the pistons seize in the bore.