Alabama CDL Class B Knowledge Test 1

It is critical that an engine have sufficient oil pressure. The engine can be destroyed rapidly if run without oil.

The added weight of a heavy load will make a vehicle sit lower than usual. A vehicle will often be taller when carrying a light load than when carrying a heavy load. If your vehicle fits under an overpass while carrying a full load, it is not guaranteed that it will fit under the same overpass if it is empty.

Factors that can affect your vehicle’s stopping distance include driving speed, the vehicle’s weight, and the slipperiness of the road surface.

When driving through work zones, you should make a particular point of reducing your speed when workers are on or near the road.

While testing for a CDL, an applicant will be required to go through a full vehicle inspection. The vehicle inspection test will include an engine oil level check.

To prevent drowsiness on a long trip, strategies include getting adequate sleep beforehand; planning out the route and stopping points in advance; driving with a passenger; and driving at times during which you are normally awake.

Check your tires regularly when looking in your mirrors. This helps ensure that you will notice a tire fire, if one should happen. Tire fires may occur when a tire is under-inflated, if dual tires are touching, or if the tires are otherwise overheated.

You should always apply the parking brake when leaving your vehicle.

Anti-Lock Braking Systems (ABS) will help you to maintain control during hard braking. ABS will not necessarily shorten your stopping distance.

When inspecting the engine compartment, you should check the oil level, coolant level, and windshield washer fluid level, among other things.

Underloading a front axle may make it impossible to safely steer your vehicle. Keep weight distribution in mind when loading cargo.

At dawn or dusk, and in snowy or rainy conditions, you should turn on your headlights to make it easier for other road users to see your vehicle.

If you must stop on the side of the road, you should turn on your emergency flashers and place the appropriate warning signals to warn other drivers.

When checking the tires as part of a pre-trip inspection, make sure the tires have sufficient tread. There should be at least 4/32 of an inch of tread in every major groove of the front tires, and at least 2/32 of an inch of tread depth on the other tires. Tire sizes should not be mismatched.

If you are found to have any detectable amount of alcohol in your system while operating a CMV but your blood alcohol concentration (BAC) is still below the legal limit of 0.04 percent, you will be put out-of-service for 24 hours. It is both illegal and dangerous to operate a motor vehicle while under the influence of alcohol.

When turning quickly to avoid colliding with a hazard in the roadway, you should always keep both hands on the steering wheel. You must have a firm grip on the wheel to be able to turn quickly.

If you see a crash involving an aggressive driver, you should stop a safe distance from the crash scene, wait for police to arrive, and inform them of the aggressive behavior you witnessed.

During the basic vehicle control skills test, you must place the vehicle in neutral and set the parking brake before exiting the vehicle to check its position. You may check the position of the vehicle no more than twice, except during the straight line backing exercise, where you may look no more than once.

In rainy weather, roads are often at their most slippery when the rain first begins to fall. Fresh rainwater mixes with oil and grease on the road to form a slick film. As the rain continues, this mixture will eventually wash away.

When loading cargo, it is important that the weight placed on each axle is neither too little nor too much. Inappropriate loading can interfere with steering, create inadequate wheel traction, or damage the axles.

When a brake pedal is pressed and the S-cam is turned, the S-cam presses the brake shoes against the inside of the brake drum. This causes friction and will cause the vehicle to slow.

After a vehicle’s engine is started, the engine’s oil pressure should rise to its normal level within seconds. Do not drive a vehicle with oil pressure that is too low.

Drivers behind you may not anticipate how slowly your CMV must travel to safely make a right turn. You can help warn them in advance by braking early and slowing gradually.

As the first step of a vehicle inspection, you should review any inspection report left by the previous driver.

A vehicle being equipped with anti-lock brakes on only the tractor or only the trailer provides additional control during braking.

When inspecting your windshield, you should look for cracks or other problems that could interfere with your ability to clearly see the road. The windshield wiper arms should be checked for proper spring tension. The wiper blades should be checked for damage, stiff rubber, and improper securement.

During the on-road driving skills test, you will be asked to pull your vehicle over to the side of the road and stop as if you were going to get out and check something on your vehicle. As you prepare to make this stop, you must check traffic; activate your turn signal; decelerate smoothly with even braking, changing gears as needed; and bring your vehicle to a full stop without coasting.

Potential warning signs of fatigue include difficulty focusing, frequent blinking, or heavy eyelids; yawning repeatedly or rubbing your eyes; daydreaming; wandering or disconnected thoughts; trouble remembering the last few miles you’ve driven; missing exits or traffic signs; having trouble keeping your head up; drifting from your lane; following too closely; hitting a shoulder rumble strip; or feeling restless and irritable.

If you are twice convicted of violating any state law regarding hand-held mobile phone use, your CDL will be disqualified. Consequences will become more severe with subsequent violations.

Texting while driving is even more dangerous than speaking on a phone while driving. In addition to being mentally distracting, texting is also physically distracting.

When driving under foggy conditions, lights cannot be taken as a reliable indication of where the road is. The lights may be coming from a vehicle that has pulled off the road.

It is always important to have enough water and antifreeze in a vehicle’s cooling system. Despite the name, antifreeze is beneficial to an engine even in hot weather.

A driver uses a look when they open their door, leave their seated position, and walk to the back of the vehicle to check its position. During the straight line backing exercise, a driver may not exceed one look. During any other exercise, a driver may not exceed two looks.

Bridges tend to freeze before other parts of the road surface. You should be especially careful on bridges when temperatures are near the freezing point.

A burning tire should be cooled with water. A driver may need to use large quantities of water to properly cool the tire.

Compressed air usually contains a certain amount of moisture and compressor oil, which can build up in the air storage tanks and damage the brake system. The tanks should be drained to clean out these accumulations. On a tank with a manual drain valve, draining should be performed at the end of each day of driving.

Even if they did not load or secure the cargo themselves, the driver of a vehicle is responsible for inspecting the cargo and ensuring that it is properly secured.

It is important to observe other drivers’ actions and identify clues that a person could be driving impaired. Drivers who have had too much to drink, are sleepy, are on drugs, or are ill can present hazards to other drivers. One sign that a driver may be impaired is that they stop in inappropriate places, such as at green traffic lights.

Signal well in advance of a turn so drivers behind you are aware of your intentions. Keep the signal on throughout the turn and turn it off once the turn is complete.

The faster you drink, the higher your blood alcohol content (BAC) will become. The liver removes alcohol from a body at a fixed rate of about one drink per hour.

Before driving a vehicle with air brakes, you should ensure that the spring brakes come on automatically when air tank pressure falls to a level between 20 and 45 psi. You can do this by chocking the wheels and releasing air from the braking system by stepping on and off the brake pedal. Once the pressure drops to an unsafe level, the parking brake valve should pop out and spring brakes should come on.

You should cover your cargo to protect people from the cargo if it spills, as well as to protect the cargo from the weather.

If you must back up, you should exit the cab and check your path for obstacles before beginning the maneuver. Drive as slowly as you can, checking your mirrors on both sides.

You must have a CDL with a HazMat endorsement to operate a vehicle that is used to transport hazardous materials.

In an air braking system, the air storage tanks can usually hold enough compressed air for the brakes to be used several times.

If you think the road surface may be becoming icy but you are not certain, you can open your window and feel the front of the side mirror, mirror support, or antenna. If ice has formed on any of these items, the road is likely becoming icy as well.

Always apply the parking brake when leaving your vehicle unattended.

Mirrors should be checked prior to the beginning of a trip. On a vehicle with a trailer, mirror adjustment can only be checked accurately if the connected trailer is straight.

Because air pressure increases with temperature, you should pay special attention to the tire mounting and pressure when traveling in hot weather.

Cargo with a high center of gravity makes a vehicle more likely to tip over than cargo with a low center of gravity. For this reason, it is important that the weight of cargo be distributed as low as possible.