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Thinking about the Doubles/Triples Trailers endorsement for your South Carolina Commercial Driver’s License (CDL)? It’s a smart move that will immediately increase your marketability and earning potential in the industry. From the rolling hills of the Blue Ridge Mountains, to the flatland of its eastern coast, you’ll see a good mix of terrain and opportunities with this addition. The main requirement is passing a 20-question multiple-choice knowledge test with a score of 80% (16 correct answers). That’s it! Since this is an addition to your CDL, you’ve already done the really hard part (the skills test). Once you pass this knowledge test, you’ll receive the “T” endorsement on your CDL, granting you the ability to legally tow two or three trailers in authorized areas (South Carolina CDL Handbook 2025).
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In the Palmetto State, you must be at least 18 years of age to add this certification to your CDL; however, federal law mandates the age requirement to travel across state lines is 21 or older. This endorsement qualifies you for pulling doubles and triples, but only double trailers are allowed in South Carolina. Fortunately, double trailers are often used throughout South Carolina for the transport of automotive parts and vehicles (Spartanburg is home to a major BMW plant), agricultural products like soybeans, peaches, poultry, and tobacco, textiles and manufacturing goods, forestry products, and consumer goods and electronics (especially near its major coastal ports). I can hear you now: “Let’s do this! But where do I start?”
Designed to simplify the task of studying for the knowledge test, our online South Carolina CDL Double/Triple Trailers Endorsement practice test offers a fine-tuned approach specific to the test material and format you’ll face at the DMV without all the excess information you will find online. Up to date as of December 2025, it includes 20 multiple-choice questions that offer instant feedback, which is a much more effective way to learn than facing all of the feedback at one time at the end.
You only need to pass the official knowledge test. When you feel fully prepared from practicing with our free tests, simply head over to the DMV and apply. Take your documents, pay the fee, pass with flying colors, and take a huge step in advancing your career to the next level.
Driver’s Ed is - nobody wants to set foot inside the DMV. That’s why millions of learners trust us for simple, visual, effective prep.
We are an officially recognized FMCSA Entry-Level Driver Training provider and a proud partner to over 2,500 libraries. We work with safety organizations like GHSA and the National Safety Council to help create safer roads for everyone.
Our trademarked system automatically saves questions you miss, creating personalized tests that target your weak spots until you’ve mastered the material.
Get smarter as you study. Our new AI-powered feedback provides detailed, question-level insights to help you understand the why behind each answer.
Go beyond the boring black-and-white manual. Our interactive handbook lets you read, listen with an MP3 audio version, or even chat with it to find the information you need, faster.
We build our practice questions from the current 2025 SC Driver Handbook and refine them using patterns recent test‑takers report.
Driver handbook • Knowledge‑test/permit overview • Fees & ID requirements • Office/appointment info
We mirror recurring themes (e.g., right‑of‑way traps, sign look‑alikes) and use similar distractors and wording styles.
We don’t collect or publish actual test items and we’re not affiliated with DMV.
