Procedures: | Reject Vehicle If: |
Service Brake Test. (a) Method (1)-On Road. At a speed of 20 mph apply service brakes firmly. Observe whether vehicle comes to a smooth stop within the distance prescribed by law; passenger cars 25 feet, type II school vehicles, light trucks, vans and multipurpose passenger vehicles 30 feet without pulling to the right or left. Driver shall have firm control of the steering wheel throughout the test. | (a) The vehicle stopping distance requires more than 25 feet for passenger cars, and 30 feet for type II school vehicles, light trucks, vans and multipurpose passenger vehicles. |
(b) Method (2)-On Road. Mount an approved decelerometer at centerline of vehicle. Level at decelerometer.At the speed of 20 mph, apply service brake firmly. Observe decelerometer reading. Determine whether vehicle pulls to right or left. | (b) Vehicle pulls to the right or left upon brake application. |
(c) A decelerometer reading of at least 17 feet psps for passenger cars, 14 psps for type II school vehicles, light trucks, vans and multipurpose passenger vehicles, or pulls to the right or left. |
Procedures: | Reject Vehicle If: |
(a) Method (3)-Platform Tester. Drive vehicle onto "drive-on-and-stop" platform tester, apply brakes firmly at a speed from 4 to 8 mph without wheel lock-up. All braking action shall take place on the platforms. Certain models of platform testing equipment are not generally sensitive enough to read the rear axle effort of front wheel drive vehicles. | (a) Readings are less than requirements on brake performance chart in §H. |
(b) These machines may be used to inspect the relative effectiveness of each wheel.There shall be braking action on all wheels. The action on any one wheel shall be 75 percent or more of the action on the other wheel on the same axle. If there is little or no braking brakes are applied with vehicle jacked action on the rear axle, jack or hoist the vehicle, apply the brakes, and attempt to turn the rear wheels. | (b) Any wheel fails to indicate braking action except as noted, or if the reading on any one wheel is less than 75 percent of the reading on the other wheel on the same axle. |
(c) Rear wheels rotate freely when brakes are applied with vehicle jacked or hoisted. |
Procedures: | Reject Vehicle If: |
(a) Method (4)-Roller-Type Brake Dynamometer (Force Measuring Type). | (a) Readings are less than requirements on brake performance chart in §H. |
(i) Adjust tire to proper inflation. (ii) Position vehicle on dynamometer rolls and begin test. (iii) Follow equipment manufacturer's recommended testing procedures. (iv) If there is little or no braking action on the rear axle, jack or hoist the vehicle and apply the brakes and attempt to turn the rear wheels. | (b) Any wheel fails to indicate braking action except as noted in procedures, or the reading on any one wheel is less than 75 percent of the reading on the other wheel on the same axle. |
(c) Rear wheels rotate freely when brakes are applied with vehicle jacked or hoisted. |
Procedures: | Reject Vehicle If: |
(a) Hydraulic System Leakage Test.While the vehicle is stopped, depress brake pedal under moderate foot force. The pedal height shall remain constant for 1 minute. | (a) Brake pedal height cannot be maintained for 1 minute. |
(b) Pedal Reserve Test.While the vehicle is stopped, depress brake pedal under moderate foot force. | (b) Less than 1/3 of the total available pedal travel remains. |
Procedures: | Reject Vehicle If: |
(a) Hydraulic System-Visually inspect condition of hydraulic system. (i) Inspect wheel cylinders for leakage and operation. Do not remove dust covers. (ii) Inspect hydraulic hoses and brake lines for leaks, cracks, chafing, flattened or restricted sections, improper support, rusting causing pitting, and improper material. (iii) Inspect master cylinder for leakage and fluid level of all sections. (Be sure no dirt gets into reservoir when cover is removed and that the gasket is serviceable.) | (a) (i) Wheel cylinder leaks or fails to operate. (ii) Hoses, or brake lines are cracked, chafed, flattened, restricted, or are rusted and pitting is visible, are improperly supported, or lines have been repaired or replaced with copper tubing or other material not designed for hydraulic brake lines. Hoses or brake lines are mounted to contact wheels or body during steering or suspension movement. (iii) Master cylinder leaks. (iv) The fluid level in any section is less than 1/2 full. (v) The gasket does not properly seal master cylinder. |
(b) Dual Hydraulic Circuits-In addition to the above, if vehicle is equipped with a brake warning light: (i) Test for operation of light; (ii) With ignition switch on, apply moderate foot force, observe light. | (b) (i) Light is burned out. (ii) Light comes on when brake and pedal is depressed. |
Procedures: | Reject Vehicle If: |
(a) Brake Drums. (i) Inspect the condition of the drum friction surface for substantial cracks extending to the open edge of the drum.(Short hairline heat check cracks should not be considered.) (ii) Inspect for cracks on the outside of the drum. (iii) Inspect for mechanical damage. (iv) Inspect for contaminated friction surface. (v) Measure inside diameter of drum. (vi) When the drum pulled has any deficiency noted, the other drum on the same axle shall also be pulled and inspected. | (a) (i) There is a substantial crack on the friction surface extending to the open edge. (ii) There is an external crack. (iii) There is evidence of excessive mechanical damage other than wear. (iv) Friction surface is contaminated with oil, grease, or brake fluid. (v) Inside drum diameter is greater than the diameter stamped on the drum, or, if the drum is not stamped, the manufacturer's maximum allowable remachining specification. If the drum is not stamped and no manufacturer's specification exists and the original diameter of the drum can be determined, the inside diameter may be no more than 0.090 inch greater than the original diameter. |
(b) Brake Discs. (i) Inspect for substantial cracks extending to edge of disc. (ii) Inspect for mechanical damage. (iii) Inspect for contaminated friction surface. (iv) When the disc brake assembly inspected has any deficiency noted, the other disc brake assembly on the same axle shall also be inspected. | (b) (i) There are substantial cracks extending to edge. (ii) There is evidence of excessive mechanical damage other than wear. (iii) Friction surface is contaminated with oil, grease, or brake fluid. (iv) Thickness of disc is less than manufacturer's recommended limit or the minimum thickness stamped on the assembly. |
Procedures: | Reject Vehicle If: |
(1) Condition of Linings and Pads. (a) Bonded Linings. Measure the lining thickness at the thinnest point. | (1) (a) Thinnest point of lining is less than 2/32 inch. |
(b) Riveted Linings. Inspect for loose or missing rivets. Measure lining thickness above rivet head at thinnest point. | (b) Any rivets are loose or missing.If lining is worn to where less than 1/32 inch remains above any rivethead. |
(c) Wire-Backed Linings. Inspect for wire showing on the friction surface of the lining. | (c) Wire backing is visible on the friction surface. |
(d) All Linings. Inspect for broken or cracked linings, and parts of linings not firmly attached to shoe. Also inspect for contamination and excessively uneven lining wear. | (d) Lining is broken, cracked, or not firmly and completely attached to shoe. Circumferential heat cracks in bonded linings are not cause for rejection if the lining is securely attached to the shoe. If friction surface is contaminated with oil, grease, or brake fluid. If lining wear is extremely uneven. |
(e) Pads (Disc Brakes). Inspect thickness of friction pads. Bonded pads-measure thinnest point of lining. Riveted pads-measure thickness of lining above rivet head. | (e) Lining on any bonded pad is less than 2/32 inch, or less than 2/32 inch lining remains above rivet head. |
Procedures: | Reject Vehicle If: |
(1) Condition of Mechanical Components. | (1) |
(a) Inspect for worn pins and missing or defective cotter pins. | (a) Mechanical parts are missing, broken or badly worn. |
(b) Inspect for broken, missing, or worn springs, cables, clevises, couplings, rods, and anchor pins. | (b) Grease retainers are leaking. |
(c) Inspect for frozen, rusted, or inoperative connections, missing spring clips, and defective grease retainers. | (c) There is excessive friction in pedal and linkage, or in brake components. |
(d) Inspect pedal shaft and bearings for high friction, wear, and misalignment. | (d) Pedal levers are improperly positioned or misaligned. |
(e) Inspect for restriction of shoe movement at backing plate and for binding between brake shoes and anchor pins. | (e) Any conversion of self-adjusting mechanism that is not completely converted. |
(f) Inspect service brake pedal rubber pads for excessive wear or missing pads. | (f) Rubber service brake pedal pad is excessively worn to expose metal pedal or rubber pad is missing. |
Procedures: | Reject Vehicle If: |
(1) | (1) |
(a) Condition of Vacuum Booster System. Visually inspect system for collapsed, broken, badly chafed, and improperly supported hoses and tubing, and loose or broken hose clamps. | (a) Hoses and tubing are leaking, collapsed, broken, badly chafed, improperly supported, or loose because of broken clamps. |
(b) Operation of Vacuum Booster System. (i) Determine if system is operating by first stopping engine than depress brake pedal several times to deplete all vacuum in system. (ii) Then depress pedal with a light force. While maintaining this force on the pedal, start engine, and observe if pedal moves slightly when engine starts. | (b) Service brake pedal does not move slightly when engine is started while pressure is maintained on pedal. |
(c) Condition of hydraulic booster system. Visually inspect system for proper fluid level, broken, kinked, or restricted hoses or lines and any leaks at the pump, steering box, booster, hoses, or lines. | (c) Fluid level in reservoir is less than manufacturer's recommendations; there are broken, kinked, or restricted hoses or lines; or there are leaks at the steering pump. |
(d) Operation of hydraulic booster system. (i) Determine if system is operating by first stopping the engine, then depress brake pedal several times to deplete all reserve pressure in the system. (ii) Then depress pedal with light force, start engine and observe if pedal moves slightly when engine starts. | (d) Service brake pedal does not move slightly when engine is started while pressure is maintained. |
Procedures | Reject Vehicle If: |
(a) Parking Brake Function. (i) Set the parking brake firmly and check the ability of parking brake to hold the vehicle. (ii) All vehicles manufactured after May 23, 1970 shall have a mechanical parking brake which will hold the vehicle to the limit of traction in either direction on a 20 percent grade. | (a) (i) Brake fails to hold the vehicle on any grade on which it is operated. (ii) A ratchet-type parking brake cannot be applied to hold the vehicle on any grade on which it is operated. |
(b) Linings and Drums. (i) If the vehicle is equipped with parking brakes which are separate from the service brakes, inspect the linings and drums in the same manner that those on the service brakes are inspected. | (b) (i) Parking brake drums are cracked, broken, or otherwise damaged. (ii) Linings are loose, worn out, or contaminated with grease, oil, or brake fluid. |
Service Brake System | EmergencyBrakeSystem | |||
Column 1 | 2 | 3 | 4 | 5 |
Braking force as a % of gross vehicle or combination weight | Deceleration in feet per second per second | Application and braking distance in feet from initial speed of 20 mph | Application* and braking distance in feet from initial speed of 20 mph | |
(1) Passenger-carrying vehicles | ||||
(a) Vehicles with a seating capacity of 10 persons or less, including driver, and built on a passenger car chassis | 65.2 | 21 | 20 | 54 |
(b) Vehicles with a seating capacity of more than 10 persons, including driver, and built on a passenger car chassis; vehicles built on a truck or bus chassis and having a manufacturer's GVWR of 10,000 pounds or less | 52.8 | 17 | 25 | 66 |
(c) All other passenger-carrying vehicles (including motorcycles) | 43.5 | 14 | 35 | 85 |
(2) Property-carrying vehicles. | ||||
(a) Single unit vehicles having a manufacturer's GVWR of 10,000 pounds or less | 52.8 | 17 | 25 | 66 |
(b) Single unit vehicles having a manufacturer's GVWR of more than 10,000 pounds except truck tractors.Combinations of a 2-axle towing vehicle and trailer having a GVWR of 3,000 pounds or less. All combinations of 2 or less vehicles in drive-away or tow-away operation | 43.4 | 14 | 35 | 85 |
(c) All other property-carrying vehicles and combinations of property-carrying vehicles | 43.5 | 14 | 40 | 90 |
* As of July 1, 1972, all vehicles subject to the regulations of the Bureau of Motor Carrier Safety, are subject to the stopping requirements in this Brake Performance Chart, except the column pertaining to Emergency Brake System*, which is effective on vehicles manufactured after July 1, 1973.
Explanation of Section H
Figure 16, TIRE CONSTRUCTION.
Figure 17, TIRE WEAR.
Md. Code Regs. 11.14.02.03