3.4.11 Brakes. Brakes shall conform to Federal Motor Carrier Safety Regulations
393.40 through 393.43 and 393.45 through 393.52. Parking brakes shall be furnished. Brake
linings shall be of nonaebestos material.
188.8.131.52 Power-hydraulic type. Class 16 vehicles shall be equipped with power assisted,
hydraulically actuated, four-wheel service brakes or with full air brakes on all wheels.
184.108.40.206.1 Split hydraulic brake system. The power-hydraulic brake system shall be so
arranged as to provide separate systems for at least two wheels and so designed and constructed
that rupture or leakage type failure of any single pressure component of the service brake system,
except structural failures of the brake master cylinder body, effectiveness indicator body, or
other housing common to the divided system, will not result in complete loss of function of the
vehicle brakes when force on the brake pedal is continued. "Pressure component" means any
internal component of the brake master cylinder or master control unit, wheel brake cylinder,
brake line, brake hose, or equivalent, except power assist components.
220.127.116.11.2 Indicator light. The split hydraulic brake system shall be equipped with an
electrically operated red light mounted on the instrument panel to indicate system effectiveness.
The light shall have an area of not less than 0.196 square inch. It shall illuminate before or upon
application of the brakes when an actuating-pressure component of the system has sustained a
loss of pressure. The indicator light system shall include a means for testing by the vehicle
operator to assure that the light bulb is operable.
18.104.22.168 Air brakes. Class 19, 28, 34.5, 36, 44 and 50 vehicles shall be equipped with
full air brakes on all wheels. The braking system, complete with all necessary components, shall
Air compressor, unloader-head type, engine driven and engine lubricated, air- or
water-cooled, and having a capacity of not less than 7.25 cubic feet per minute
(cfm) for class 16, 19 and 28 vehicles and 12 cfm for class 34.5, 36, 44 and 50
Air storage reservoir(s), each tank equipped with drain, and with safety and check
valves between compressor and last reservoir tank. When a pneumatic fuel product
tank control system is furnished, the air storage reservoir(s) shall be of sufficient
capacity to supply air for both the air brake system and the complete tank
pneumatic control system.
Foot control, suspended or treadle type
Air control valves
Low air pressure warning, visible and audible
Service brake stop lamp switch
Automatic moisture ejector