California Class A CDL Practice Test (CA) 8

4.9 out of 5 (159 votes)
80% Passing score
50 Questions
10 Mistakes allowed
Dive into your preparation for the California Class A CDL with our detailed eighth practice test. Tailored specifically for aspiring Class A CDL holders, this DMV practice test serves as an essential tool in your training arsenal. It comprises 50 questions that span a broad spectrum of necessary knowledge, from pre-trip vehicle inspections to mastering gear shifts, including downshifting, and navigating hills and steep downgrades. You'll also encounter scenarios on effective communication with other drivers, speed control, and vital drug and alcohol awareness. Our California class A CDL practice test stands out for its realistic approach. Designed to closely mimic the actual CDL written test, it ensures you're not just memorizing answers but truly understanding the concepts. Each attempt at the California CDL general knowledge test presents the same set of questions, allowing you to gauge your progress and identify areas for improvement. What sets our practice test apart is the valuable end-of-test summary feature. After completing the test, you'll receive a detailed report highlighting the questions you missed, along with the correct answers. This immediate feedback is instrumental in enhancing your learning and retention. Moreover, we believe quality education should be accessible to everyone. That's why our California CDL Class A Practice Test is completely free. It offers the same features and learning opportunities as any paid version, without the financial burden. Finally, our commitment to accessibility means you can access our practice tests anywhere, anytime. Whether you're on a desktop, a mobile device, or using our mobile app, these resources are always at your fingertips, ensuring your preparation for the California Class A CDL is uninterrupted and convenient.
FREE CDL Practice Test App
Pass your California CDL General Knowledge test with the NextDoorDriving app. Real questions and answers—100% free and ad-free.
Download on the App Store

Sample California CDL Test Questions - General Knowledge

Question 1

If a commercial motor vehicle power unit uses reflective triangles as its stopped-vehicle warning devices, how many must it carry?

  1. A 1
  2. B 2
  3. C 3
  4. D 4

Correct answer: C – 3

Federal equipment rules require three bidirectional emergency reflective triangles when triangles are used as the required warning devices. California's commercial handbook likewise instructs drivers to check for three red reflective triangles during the vehicle inspection. The triangles must be carried on the power unit and ready for use if the vehicle becomes stopped on or beside a roadway.

Source: California Commercial Driver Handbook — § 2.1.5, “Check the Emergency Equipment”, 49 CFR § 393.95(f)(1) – Emergency equipment on all power units

Question 2

Wet brakes caused by heavy rain or standing water may result in which problems?

  1. A Wheel lockup
  2. B A trailer jackknife
  3. C Pulling to one side
  4. D All of the above

Correct answer: D – All of the above

Water can make brakes weak, cause them to apply unevenly, or make them grab. These conditions may reduce braking power, lock the wheels, or pull the vehicle toward one side. If the vehicle is towing a trailer, uneven or grabbing brakes can also contribute to a jackknife. The brakes should be dried and tested after passing through deep water.

Source: California Commercial Driver Handbook — § 2.13.2, “Wet Brakes”

Question 3

The handbook prohibits overhang or tailgate loads involving which hazardous-material classes?

  1. A Class 1 explosives
  2. B Class 4 flammable solids
  3. C Class 5 oxidizers
  4. D All three classes

Correct answer: D – All three classes

The California handbook prohibits overhang or tailgate loads of Class 1 explosives, Class 4 flammable solids, and Class 5 oxidizers. These materials must be loaded in a closed cargo space unless all packages are fire- and water-resistant and are covered with a fire- and water-resistant tarp. The restriction applies to all three listed hazard classes.

Source: California Commercial Driver Handbook — § 9.4.1, “Use Closed Cargo Space”

Question 4

A see-through coolant container is not part of the pressurized cooling system. What may you do while the engine is at operating temperature?

  1. A Check the level and remove the container cap to add coolant
  2. B Remove the radiator cap immediately
  3. C Use only plain water in the cooling system
  4. D Open any pressurized cooling-system fitting

Correct answer: A – Check the level and remove the container cap to add coolant

A sight glass or see-through recovery container allows the coolant level to be checked while the engine is hot. If that container is not part of the pressurized system, its cap may be removed and coolant added at operating temperature. Never remove the radiator cap or another pressurized component until the system has cooled because hot steam and coolant can cause severe burns.

Source: California Commercial Driver Handbook — § 2.14.1, “Engine Coolant”

Question 5

What are the two air lines found on an air-braked combination vehicle?

  1. A Service and emergency lines
  2. B Service and foundation-brake lines
  3. C Brake and reservoir lines
  4. D Pressure and return lines

Correct answer: A – Service and emergency lines

Combination vehicles have a service air line and an emergency air line. The service line, also called the control or signal line, carries pressure controlled by the brake pedal or trailer hand valve. The emergency line, also called the supply line, fills the trailer air tanks and causes the trailer emergency brakes to apply if pressure in that line is lost.

Source: California Commercial Driver Handbook — § 6.2.4, “Trailer Air Lines”

Question 6

Water should not be used on which of these vehicle fires?

  1. A A gasoline fire only
  2. B An electrical fire only
  3. C Both gasoline and electrical fires
  4. D Neither type of fire

Correct answer: C – Both gasoline and electrical fires

Do not use water on a gasoline fire because it can spread the burning liquid and flames. Water should also be avoided on an electrical fire because it can conduct electricity and cause shock. Use an extinguisher rated for the fire involved, such as an appropriate B:C or A:B:C extinguisher, rather than applying water indiscriminately.

Source: California Commercial Driver Handbook — § 2.21.3, “Use the Correct Fire Extinguisher”

More California CDL Practice Tests
Other CDL Endorsements