1993 Pontiac Grand Am Owner's Manual - Page 226

Brake Master Cylinder Your brake master cylinder is here. It is filled with DOT-3brake fluid. There are only two reasons why the brake fluid level in your master cylinder might go down. The first is that the brake fluid goes down to an acceptable level during normal brake lining wear. 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. If it is, you should have your brake systemfixed, since a leak means that sooner or later your brakes won't work well, or won't work at all. So, it isn't a good idea to"top off' your brake fluid. Adding brake fluid won't correct a leak. If you add fluid when your linings are worn, then you'll have too much fluid whenyou get new brake linings. You should add (or remove) brake fluid, as necessary, only when work is done on the brake hydraulic system. 225 ...