Brake Master Cylinder - GMC SIERRA 1994 Manual

Brakes
Brake Master Cylinder
Your brake master
cylinder is here. It is
filled with DOT-3
brake 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 system fixed, 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 when you get new brake linings. You should add
(or remove) brake fluid, as necessary, only when work is done
on
the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to check your brake
fluid. See "Periodic Maintenance Inspections" in the Index.
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