GMC 2003 Yukon Denali User Manual page 326

Checking Brake Fluid
You can check the brake fluid without taking off the cap.
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 Lubrjcaats
on page 6- 15.
Just look at the brake fluid reservoir. The fluid level
should be above MIN. If it isn't have your brake system
checked to see if there is a leak.
After work is done on the brake hydraulic system, make
sure the level is above the MIN but not over the MAX
mark.
Always clean the brake fluid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from enterinc ++e reservoir.
I
With the wrong kind of fluid in
yo^.
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.
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