If your vehicle has hydraulic brakes, there is a brake master cylinder. Refer to the Maintenance Schedule to determine when to check your brake fluid.

Caution: Do not add brake fluid before checking the level or there could be too much brake fluid. Brake fluid could spill on the hot engine and it can catch fire. You could be burned and the vehicle could be damaged. See "Checking Brake Fluid" in this section.

Checking Brake Fluid

Apply the brake pedal several times with the ignition off. Then clean one of the reservoir caps and the area around the cap, and remove it. The fluid level should be even with the bottom ring of the filler opening.

If it is low, add enough fluid to fill the reservoir to the proper level.

What to Add

Use the proper fluid listed in your Maintenance Schedule. Use new brake fluid from a sealed container only.

Always clean the brake fluid reservoir cap and the area around the cap before removing it. This will help keep dirt from entering the reservoir.

Caution: With the wrong kind of fluid in the brake hydraulic system, the brakes might not work well. This could cause a crash. Always use the proper brake fluid.

Notice: 

The brake drums should be removed and inspected each time the tires are removed for rotation or changing. When you have the front brakes replaced, have the rear brakes inspected, too.

Brake linings should always be replaced as complete axle sets.

See your dealer if the brake pedal does not return to normal height, or if there is a rapid increase in pedal travel. This could be a sign of brake trouble.

Every time you make a brake stop, your brakes adjust for wear.

Your vehicle has four-wheel disc brakes.

Some driving conditions or climates may cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with your brakes.

Brake linings should always be replaced as complete axle sets.

The braking system on a vehicle is complex. Its many parts have to be of top quality and work well together if the vehicle is to have really good braking. Your vehicle was designed and tested with top-quality brake parts. When you replace parts of your braking system -- for example, when your brake linings wear down and you need new ones put in -- be sure you get new approved replacement parts. If you do not, your brakes may no longer work properly. For example, if someone puts in brake linings that are wrong for your vehicle, the balance between your front and rear brakes can change -- for the worse. The braking performance you have come to expect can change in many other ways if someone puts in the wrong replacement brake parts.

If your vehicle has air brakes, it is important to get rid of moisture in your system. Moisture will damage your system if it is not removed daily.

There are two ways to do this. One is automatic if your air-brake vehicle has the optional moisture ejector. If your vehicle does not have that option, you must drain the air reservoirs every day.

Drain them at full system pressure. To be sure you are at full pressure, check your air pressure gage. It should read at least 100 psi (692 kPa).

If you have air brakes with a moisture ejector, the valve automatically ejects moisture from the reserve tank when the air compressor cycles.

If your vehicle has air brakes, it may have an air dryer. This collects and removes dirt, moisture or other foreign matter from the air prior to entering the brake system. It is mounted on the passenger's side frame rail.

If your dryer is a Bendix-Westinghouse, it has a filter that you need to change at intervals. See Scheduled Maintenance for more about servicing this filter.

Your vehicle may have an electric air compressor. This compressor is used to run options that require pressurized air, such as air horn, air seat, exhaust restrictor or an exhaust brake.

The air compressor is used when vehicles are not equipped with an air brake system.

The air supply for this system must be maintained by releasing the drain valve to eject any moisture that may have built up in the system.

It is recommended that this system be drained on a weekly basis.

If you have a manual transmission, your clutch will need adjustment when pedal free travel gets down to about 1/4 inch (32 mm), as measured at the clutch pedal pad. You should have 1 1/2 to 2 inches (38 to 51 mm) of clutch pedal free travel. See Scheduled Maintenance for more information.

If you have an electric/hydraulic parking brake, a good time to check the fluid level is when you check the fluid levels under the tilt cab. The fluid reservoir is located in the component box beneath the driver's side of the cab on the frame rail.

If you need to add fluid, use Dexron® III Automatic Transmission Fluid. See Scheduled Maintenance .

First, apply the parking brake. To check the fluid level, look at the MAX and MIN lines on the side of the reservoir. If the level is below the MAX line, add fluid. To add fluid, clean away any dirt around the reservoir cap. Remove the reservoir cap and add enough fluid to bring it up to the MAX level.