1993 Buick Regal Owner's Manual - Page 235

Brake Master Cylinder Your brake master cylinder is here. is filled with It DOT-3 brake fluid. There are only two reasons the brake fluid level why in your master cylinder might @down. The first that the is brake fluid goes down to acceptable level during an normal brake liningwear. When new linings are put in, the fluid level goes back up. The other reason is that fluid is leaking out of the brake system. it is, you If should haveyour brake system fixed, since a leak means that sooner or later your brakes won't work well, or 233