California CDL DMV Knowledge Test Class B 1

Commercial vehicle drivers are prohibited from consuming any intoxicating beverage, regardless of its alcohol content, within four hours of going on duty.

For safe operation, a commercial motor vehicle needs a tread depth of 4/32 of an inch in every major groove on the front tires, and a tread depth of 2/32 of an inch on other tires.

If used and maintained properly, air brakes are a safe and effective way to stop large, heavy vehicles.

When backing with a trailer, begin by turning the steering wheel in the direction opposite of the turn. Once the trailer starts to turn, reverse the direction of the steering wheel to follow the trailer.

While driving downhill, you should hold down the brake pedal until your vehicle reaches a speed 5 mph below your safe speed, then release the brake pedal. Repeat this process.

When backing, you should pull forward to reposition your vehicle whenever needed. Drift should be corrected immediately by turning the steering wheel in the direction of the drift.

When involved in an accident, you should protect the area, notify authorities, care for the injured, collect required information, and report the accident. You can lose your license for leaving the scene of an accident.

Parking brakes should be used whenever you park. If necessary, chock your wheels.

When backing with a trailer, begin by turning the steering wheel in the direction opposite of the turn. Once the trailer starts to turn, reverse the direction of the steering wheel to follow the trailer.

When planning to turn left at an intersection, make sure you have reached the center of the intersection before beginning the turn. If you turn too soon, off-tracking may cause the left side of your vehicle to hit another vehicle.

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.

Braking after a tire fails can result in a loss of control. Stay off your brakes, if possible, until your vehicle has slowed considerably.

When doing a pre-trip inspection during the winter, you should pay extra attention to the coolant level and amount of antifreeze; the defrosting and heating equipment; the wiper blades and windshield washer; the tires and tire chains; the lights and reflectors; the windows and mirrors; the hand holds, steps, and deck plates; the radiator shuttles and winterfront; and exhaust system.

When braking a vehicle equipped with an Anti-Lock Braking System (ABS), you should not brake any differently than you would if driving a vehicle with a different braking system.

Truck tractors with air brakes built on or after March 1, 1997 are required to be equipped with Anti-Lock Braking Systems (ABS).

When examining the engine compartment during a pre-trip inspection, you should check the engine oil level, the radiator coolant level, and the condition of the hoses.

Rough acceleration can cause mechanical damage, so be sure to accelerate smoothly and gradually.

If you find yourself being tailgated by another driver, you should increase your following distance and avoid making quick moves. Increasing your speed may only result in the other driver continuing to tailgate you at a higher speed. Do not turn on your taillights or flash your brake lights at the other driver.

If you see, hear, smell, or feel anything while driving that does not feel right, you should have it checked out.

To reduce the risk of becoming fatigued on a long trip, you should stop to take a break at least once for every two hours or 100 miles driven.

Most states have an Implied Consent Law, which means that by driving a vehicle on the state's roads, you have agreed to undergo a drug or alcohol test if a police officer asks you to do so. If you refuse to submit to a test, you will lose your operating privileges. Make sure you are aware of the laws for every state in which you drive.

Federal and state laws require drivers to inspect their vehicles before every trip, regardless of length.

Driving in fog is always dangerous and should be avoided entirely if at all possible. If you must drive in fog, be sure to turn on your low beam headlights and fog lights, even during the daytime.

To reduce the risk of developing aggressive driving behavior, you should take measures to manage your stress. One strategy to do this is to simply take a deep breath and accept your circumstances if you realize you will be late to your destination.

Tar in road pavement often rises to the surface of the road, or "bleeds," in very hot weather. Watch for such areas because they can be very slippery.

To avoid a loss of control, you should accelerate slowly when driving in poor-traction conditions, such as rain or snow.

An Individual Vehicle Distance Record (IVDR) must include information about the distance traveled by a vehicle and the amount of fuel purchased. The required distance information includes the dates of a trip and the total distance traveled by the vehicle.

B:C fire extinguishers are designed to work on electrical fires and burning liquids. Don't pour water on an electrical fire.

Wheels or rims that have had welding repairs are not safe for use. They should be replaced before the vehicle is taken on the road.

Poorly balanced weight in a trailer can make handling unsafe. For example, either too little or too much weight on the front axle can make a vehicle difficult to steer. Weight should be distributed evenly from front to back and from side to side. It should be distributed as low as possible.

Tire load is defined as the maximum safe weight that a tire can carry at a specified pressure.

Cargo should be inspected before beginning a trip, within the first 50 miles of the trip, and every three hours or 150 miles traveled thereafter. Cargo should be inspected every time the driver stops to take a break. The driver of a truck transporting cargo is responsible for the cargo being safely secured throughout the trip.

It is best to avoid driving through large puddles or moving water. If there is no way to avoid driving through water, you should slow down, shift into a low gear, and gently apply the brakes. Pressing linings against the brake drums or discs will keep water, mud, silt, and sand from getting inside the brake mechanisms.

Before driving a vehicle with a dual air brake system, allow time for the air compressor to build up a minimum of 100 psi pressure in both the primary and secondary systems. Watch the air pressure gauges to monitor the pressure levels.

As you exit your vehicle during the basic vehicle control skills test, you must face the vehicle and maintain three points of contact at all times. If your testing vehicle is a bus, you must maintain contact with the handrail. Exiting the vehicle incorrectly may result in automatic failure of the basic control skills test.