Chevrolet 2003 Monte Carlo Owner's Manual page 279

There are only two reasons why the brake fluid level in
the reservoir 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 o f f 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 brak 'lydraulic system.
When your brake fluid falls to a low level, your brake
warning light will come on. See Brake System Warning
Light on page 3-31.
What to Add
When you do need brake fluid, use only DOT-3 brake
fluid. Use new brake fluid from a sealed container
only. See Part D: Recommended
Fluids
and Lubricants
on page 6- 15.
Always clean the brake fluid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from eni 'ng the reservoir.
. .
you have too much b <e fluid,
_ _
;an spill on
the engine. The fluid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work is done on the brake
hydraulic system.
With the wrong kind of fluid in your brake
system, your brakes may not work well, or
they may not even work at all. This could
cause a crash. Always use the proper
brake fluid.
5-44