Free TN CDL Double/Triple Trailers Practice Test 2026

Since you’re here, you’re probably exploring the option of adding a Double and Triple Trailers endorsement to your Tennessee Commercial Driver’s License (CDL). This is an outstanding step toward expanding the scope of your transport offerings and significantly increasing your earnings potential. Home to the Appalachian Mountains, you’ll find rolling hills and flatlands as you pull doubles in Tennessee and you’ll have a competitive edge against other drivers lacking this endorsement. All you need to do is pass a 20-question multiple-choice knowledge test with a score of 80% (16 correct answers). Once you’ve passed, the “T” endorsement on your CDL will authorize you to pull two or three trailers in areas that allow it (Tennessee CDL Handbook 2026).

In the Volunteer State, you must be at least 18 years of age to add this certification to your CDL. For the younger folks just getting started, keep in mind that the age requirement to travel across state lines is 21 or older. For everyone, while the Double/Triple Trailers endorsement authorizes you to pull both doubles and triples, you are restricted to only pulling doubles in Tennessee. Rest assured though, double trailers are often used throughout Tennessee for the transport of automotive parts and vehicles (Nissan and General Motors have major manufacturing plants in Smyrna and Spring Hill, respectively), agricultural products like soybeans, corn, cotton, and livestock, whiskey and spirits (Lynchburg is a major producer), consumer goods and electronics, and forestry and paper products. By this point, you’re probably saying, “I’ve got to have this! But how do I get ready for this test?”