Maryland CDL: General Knowledge Practice Test

Not quite. The answer is use the braking effect of the engine.

When you drive down long, steep downgrades, the braking effect of your engine is what's most important, and your service brakes are only a supplement to being in the proper low gear. They cannot compensate for your vehicle being in an unsafe high gear without putting too much pressure on your brakes. Save your brakes so you will be able to slow or stop as required by road and traffic conditions.

Not quite. The answer is involves keeping a vehicle in a straight line when braking.

In controlled braking, you apply the brakes as hard as you can without locking the wheels, keeping movement of the steering wheel to a minimum.

Not quite. The answer is Upon exiting a tunnel

Inside a tunnel, you don't feel the effect of crosswinds pushing you sideways. But once you emerge from the tunnel into an open space, the crosswinds will suddenly hit you. If your vehicle is traveling alongside another vehicle, there is some chance that the crosswinds will push one of the vehicles against the other.

Not quite. The answer is Gauges, brakes, lights, tires, and cargo securement

During a trip, keep an eye on your gauges for signs of trouble. Whenever you stop, check such safety-critical items as the brakes, lights, tires, wheels, cargo securement devices if any, and trailer coupling devices if you're pulling a trailer.

Not quite. The answer is Steering arm

Component G is the steering arm. It connects the drag link to the tie rod.

Not quite. The answer is You

After motioning you over, the first thing the DOT inspector will do is walk up to your cab and look at you and the cab interior. The inspector will note whether you're wearing your seatbelt. He or she will check if you look like you've been dozing off. He or she will see or smell whether you've been smoking marijuana or drinking alcohol. Before starting the inspection of your truck, the inspector will ask to see your logbook.

Not quite. The answer is There are blind spots that your mirrors cannot show you.

Mirrors can show a great deal around your vehicle, but there are still blind spots that you can't see. Keep an eye on all the vehicles around you that you can see, in case one of them starts to move into one of your blind spots. Also use a helper when backing.

Not quite. The answer is Yes, as long as the engine isn't overheated.

Some vehicles have sight glasses, see-through coolant overflow containers, or coolant recovery containers. These permit you to check the coolant level while the engine is hot. If the container is not part of the pressurized system, the cap can be safely removed and coolant added even when the engine is at operating temperature. Never remove the radiator cap or any part of the pressurized system until the system has cooled.

Not quite. The answer is Mirrors

In the North American Standard Out-of-Service Criteria, by CVSA, the critical vehicle inspection items are the most critical systems in the vehicle. These are the brakes, the cargo securement, the driveline, the suspension, the steering, and others. Mirrors are not considered a critical vehicle inspection item. To pass inspection, the vehicle must not have any defects in any of these critical vehicle inspection items. Furthermore, if inspectors discover a defect in one of these items that is likely to cause a crash or breakdown, they will place the vehicle out of service.

Not quite. The answer is All of the above

A skid occurs when the tires lose their grip of the road. This can happen in any of four ways: (1) Over-braking: Braking too hard and locking the wheels. Skids can also occur if you use the speed retarder on a slippery road. (2) Over-steering: Turning the wheels more sharply than the vehicle can turn. (3) Over-acceleration: Supplying too much power to the drive wheels, causing them to spin. (4) Driving too fast: Most serious skids result from driving too fast for road conditions.

Not quite. The answer is are unstable loads.

Dry bulk and hanging meat cargoes have high centers of gravity. Plus, hanging meat sways significantly when you're driving on a curve, making for a very unstable load.

Not quite. The answer is To shift into a low gear when you're stopped

When driving a CMV with an unsynchronized manual transmission, you can shift gears by double clutching or floating the gears. To shift into low gear or reverse when your vehicle is stopped and the engine is idling, you can engage the clutch brake. This stops the transmission's input shaft (connected to the engine) from rotating, so you can smoothly shift into low gear or reverse. To engage the clutch brake, depress the clutch pedal all the way to the floor. Never engage the clutch brake while your vehicle is moving; doing so can damage the clutch brake.

Not quite. The answer is All of the above can work.

Today, most vehicles with ABS have a light on the instrument panel that will light up briefly when the vehicle is started to alert you about the ABS. Or you can check for wires from your brakes.

Not quite. The answer is Both of the above

Underinflated tires, dual tires that touch, and loose fuel connections are just some of the things that can start a fire.

Not quite. The answer is compression stroke.

Most trucks on the road today have four-stroke diesel engines. During the intake stroke, the downward motion of the piston pulls fresh air into the cylinder. During the compression stroke, the upward motion of the piston compresses the air. This causes the temperature of the air to rise sharply. Toward the end of the compression stroke, the fuel injector sprays fuel into the hot compressed air. The fuel-air mixture is now hot enough to ignite. As the power (combustion) stroke begins, fuel continues being injected, and the combustion of the fuel-air mixture produces energy to push the piston downward again.

Not quite. The answer is politely refuse.

The safety of the cargo is your responsibility. Never allow anyone who is unauthorized by your carrier to drive your truck. The person may be planning to drive off with your truck. Evidently, it's happened before.

Not quite. The answer is False

If there's a fire under the hood, opening the hood will allow more oxygen to reach the fire, which can make the fire worse. Instead, try to shoot extinguishing foam through louvers or the radiator, or from the vehicle’s underside.

Not quite. The answer is Cab air conditioning

During Step 4 (Turn Off Engine and Check Lights) of the Seven-Step Inspection Method, check your headlights and four-way flashers. During Step 5 (Walk-Around Inspection), check that your cargo is secure and its weight is evenly distributed. While it's nice to be comfortable during your trip, checking the performance of the cab air conditioner isn't part of the Seven-Step Inspection Method.

Not quite. The answer is provide enough traction to steer and push the vehicle through snow.

Snow-covered road surfaces provide much less traction than dry surfaces. Your tires must provide enough traction to maneuver your vehicle on snow safely. Under federal regulations, your front tires must have a tread depth of at least 4/32 inch, and all other tires must have a tread depth of at least 2/32 inch. For best traction, however, make sure that the treads are even deeper before you try to drive on snow.

Source: 49 CFR 570.62

Not quite. The answer is To tighten tiedown chains

A load binder (also known as a chain binder) is used to tighten a tiedown chain so the load can't shift. Some load binders are tightened with a lever; others use a ratchet mechanism.