Buick Verano Owner's Manual page 271

The brake/clutch fluid can be
checked without taking off the cap
by looking at the brake/clutch fluid
reservoir.
The fluid level should be above
MIN. If it is not, have the brake/
clutch hydraulic system checked to
see if there is a leak.
After work is done on the brake/
clutch hydraulic system, make sure
the level is above MIN but not over
the MAX mark.
When the brake/clutch fluid falls to
a low level, the brake warning light
comes on. See
If the vehicle has DOT 3 brake
fluid, as indicated on the reservoir
cap, use only new DOT 3 brake
fluid from a sealed container.
See
If the vehicle has DOT 4 brake fluid,
as indicated on the reservoir cap,
use only new DOT 4 brake fluid
from a sealed container. It is
recommended that the brake/clutch
hydraulic system be flushed and
refilled with new DOT 4 fluid at a
regular maintenance service every
two years. See
Always clean the brake/clutch
fluid reservoir cap and the area
around the cap before removing it.
This helps keep dirt from entering
the reservoir.
.
With the wrong kind of fluid in the
brake/clutch hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake/clutch fluid.
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and
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