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SC CDL Air Brakes Practice Test 4 2025

Perfect for first-time and renewal CDL/CLP applicants, and those adding endorsements.

Our South Carolina DMV CDL Air Brakes Practice Tests give you the surest path to passing your Air Brakes Knowledge Exam on the first attempt. Until you pass the official test, your CDL will carry the “L” restriction, which will prohibit you from operating commercial motor vehicles with air brakes, significantly limiting your employment opportunities. If you fail the test, South Carolina requires a one-day waiting period and a fee before retesting. Because most commercial motor vehicles (CMVs) rely on air brakes, this restriction closes the doors to many jobs in the Palmetto State.

From the ports around Charleston, the manufacturing out of Spartanburg, and the distribution networks along I-26, I-85, and I-95, companies depend on drivers who are air brake-qualified. Major industries reliant on air brake-qualified drivers include agriculture, automotive equipment manufacturing, chemicals and raw materials handling, courier services, distribution and warehousing, manufacturing and industrial production, port and maritime logistics, specialized freight and tanker operations, and transportation and logistics. Major companies in the area that regularly hire air brake-qualified drivers include AR&D Trucking Company Inc., Carolina Logistics Inc., Carey Moving and Storage, Dedicated Transportation Solutions, Estes Express Lines, Randolph Trucking, Service Transportation, Inc., Southeastern Freight Lines, and Tri Star Freight System Inc.

A minimum 80% passing grade requirement is in place for the knowledge exam. With so many opportunities available and so many delays and added fees if you don’t pass, our Air Brakes Practice Tests are exactly what you need to pass on your first attempt. Our practice tests mirror the official exam and are designed to familiarize you with the sometimes tricky wording, distractors, and double negatives often found on the official exam. For each response, you will receive AI-driven feedback helping you retain more information as you go and learn the material faster. Our practice tests also feature an interactive CDL Manual and our revolutionary Challenge Bank of questions that remembers any you miss and presents those questions repeatedly until you answer them correctly. With our preparation materials, you will enter the official testing site ready for anything they throw at you. Try another practice test here: https://driving-tests.org/south-carolina/sc-cdl-air-brake-practice-test/.

Pass the first time, lift the “L” restriction, and open the Palmetto State doors wide open to new job opportunities. Consider adding valuable endorsements to your CDL, such as (N) Tanker, (H) Hazardous Materials, and (T) Doubles/Triples. Our Practice Tests can help: https://driving-tests.org/south-carolina/sc-cdl-hazmat-practice-test/. Also, consider preparing for the official combination exam with our Combination Vehicles Practice Tests: https://driving-tests.org/south-carolina/sc-cdl-combination-test/.

Real exam-style pitfalls you’ll practice:
Common Traps
Distractors
Trick Wording
Double Negatives
SC CDL Air Brakes Practice Test 4 2025
Commercial Driver's License
Based on official SC exam questions
Steven Litvintchouk, M.S., Chief Educational Researcher at Driving-Tests.org

Authored and fact-checked by Steven Litvintchouk, M.S.

Chief Educational Researcher, Driving‑Tests.org (ACES member)
Last verified for accuracy on
Methodology & Editorial Policy

9 min to complete
Available in EN and ES

What to expect on the actual SC permit test

25

questions

20

correct answers to pass

80%

passing score

More SC CDL test resources

  1. Air Brakes Test 1
  2. Air Brakes Test 2
  3. Air Brakes Test 4 (you are here)

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