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A white semi tractor fulling two trailers near a mountain

Need a quick overview? The Doubles/Triples (T) Endorsement is essential for CDL holders planning to drive vehicles towing two or three trailers. It confirms your ability to handle these larger and more complex combinations safely.

What is a Doubles/Triples Endorsement?

This endorsement qualifies CDL holders to drive commercial vehicles pulling double or triple trailers, a requirement for certain transport roles. It’s crucial for jobs that involve transporting multiple trailers, focusing on the skills needed to manage the extra length and weight.

Quick Facts

Knowledge TestFocus on specifics of handling doubles/triples, including safety procedures.
Skills TestPractical driving test with double or triple trailers.
State RequirementsAdditional qualifications or endorsements as per state rules.
Renewal PeriodTypically aligns with CDL renewal, varies by state.
Weight RestrictionsSpecific limits based on state regulations and trailer types.

How to Acquire a Doubles and Triples Endorsement: 4 Steps


Start with Your CDL

Ensure you have a valid CDL as a prerequisite to obtaining the endorsement.


Pass Your Knowledge Test

Study and pass a Doubles/Triples written test (20 questions, 80% passing rate) on operating doubles and triples, focusing on safety, coupling/uncoupling, and vehicle handling.


Pass Your Practical Skills Assessment

Pass the skills test to demonstrate your ability to safely handle double or triple trailer setups in various driving conditions.


Fulfill State-Specific Criteria

Fulfill any additional requirements or endorsements as per state rules.

Sample Test Questions for the Doubles/Triples Endorsement

Prepare for your endorsement test with these sample questions:

  1. In a set of triples, where should the heaviest trailer be? The heaviest trailer should be the closest to the power unit to maintain stability.

  2. Why should you never disconnect the pintle hook with the dolly still under the rear trailer? Disconnecting the pintle hook without removing the dolly can lead to a loss of control or cause the dolly to flip up, potentially causing injury or damage.

  3. What is it called when the rear wheels follow a different path than the front wheels when a vehicle goes around a corner? This is known as ‘off-tracking’ or ‘cheating’, and it is more pronounced with longer vehicles or those pulling trailers.

Use these questions as a guide to prepare for your exam and familiarize yourself with the types of questions that will be asked. Get ready for your endorsement test with our extensive selection of free Doubles and Triples endorsement practice questions. Begin your practice now to enhance your chances of passing the CDL endorsement exam.

Key Exam Topics for the T Endorsement

Common Questions About the T Endorsement

Quick Tip: Adding a “T” endorsement to your CDL is relatively easy and can significantly boost your career opportunities. It only requires passing a knowledge test and, in some cases, a practical driving test.

Secure your CDL with confidence! Our comprehensive guide and resources are designed to help you succeed. Visit Driving-Tests.org for practice tests and more information tailored for the T Endorsement.

Professional Insight: Gaining hands-on experience under guidance or through specialized training courses is invaluable for building proficiency in handling doubles and triples.

The Doubles/Triples Endorsement is a key addition to your CDL, opening doors to specialized transport roles. Adequate training and knowledge of handling these complex vehicle setups are essential for safe and efficient operation. Explore Driving-Tests.org for more resources and practice tests tailored for the T Endorsement.

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