1995 Buick Roadmaster Owner's Manual - Page 238

Brakes Brake Master Cylinder Your brake master cylinderis here. It is filled with DOT-3 brake fluid. the fluid level goes back up. other reasonis that The fluid is leaking outof the brake system.If it is, you should have your brake system fixed, since a means leak that sooner or later your brakes won't work well, or won't work at all. So, it isn't a goodidea to "top off' your brake fluid. Adding brake won't correct a fluid leak. I you add fluid when your linings are worn, then f you'll have too much fluid when younew brake get linings. You should add (or remove) brake fluid, as necessary, only when workis done on the brake hydraulic system. There are only two reasons why the brake level in fluid go your master cylinder might down. Thefirst is that the brake fluid goes down to an acceptable level during are normal brake lining wear. When new linings put in, Refer tothe Maintenance Schedule to determine when to check your brake fluid. See "Periodic Maintenance Inspections'' in the Index.