The brake master cylinder and, on manual transmission vehicles, the clutch hydraulic system use the same reservoir. See Engine Compartment Overview for the location of the reservoir. The reservoir is filled with either DOT 3 or DOT 4 brake fluid as indicated on the reservoir cap.
The fluid level must be between the MIN and MAX marks.
There are only two reasons why the fluid level in the reservoir might go down:
Do not top off the brake/clutch fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are worn, there will be too much fluid when new brake linings are installed. Add or remove fluid, as necessary, only when work is done on the brake/clutch hydraulic system.
Warning
If too much brake fluid is added, it can spill on the engine and burn, if the engine is hot enough. You or others could be burned, and the vehicle could be damaged.
Add brake fluid only when work is done on the brake/clutch hydraulic system.
When the brake fluid falls to a low level, the brake warning light comes on. See Brake System Warning Light
What to Add
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 Recommended Fluids and Lubricants
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. See Recommended Fluids and Lubricants
It is recommended that the brake/ clutch hydraulic system be flushed and refilled with new fluid at a regular maintenance service interval. See Maintenance Schedule . 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.
Warning
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.
Caution