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Free CDL Doubles and Triples Practice Test
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Your result
The knowledge-test pass mark is 80% under 49 CFR 383.135. This independent practice score does not predict an official result.
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What should I study for the CDL doubles and triples test?
Study assembly and hookup, placement of the heaviest trailer, off-tracking, sway, rollover and yaw in steady turns, and the traffic problems a long combination creates. 49 CFR 383.93 requires a knowledge test, not a skills test. The section does not say where the heaviest trailer must sit. These questions are not the state exam.
Topics in this set
Hookup, heaviest-trailer placement, stability, and the traffic effects of a long combination.
20 questions · Practice mode
Last source review: . Source editions and limits are described below.
10 sample questions and answers
Read these examples here, or practice the full set above. The wording is independent study material based on federal sources.
Which test does 49 CFR 383.93 require for a double/triple trailers endorsement?
Answer: A knowledge test
Doubles and triples are the knowledge-test row, unlike passenger and school bus.
Report a problem with this questionMust a driver obtain a state endorsement to operate double or triple trailers?
Answer: Yes
Double/triple trailers are a listed endorsement description.
Report a problem with this questionMay a commercial learner’s permit carry the doubles and triples endorsement?
Answer: No
The CLP endorsement list is passenger, school bus, and tank vehicle.
Report a problem with this questionIs the procedure for assembly and hookup of the units a required doubles/triples knowledge topic?
Answer: Yes
Assembly and hookup is the first knowledge item.
Report a problem with this questionDoes the doubles/triples knowledge test include proper placement of the heaviest trailer?
Answer: Yes
The section requires knowledge of that placement. It does not print one diagram of where the heaviest trailer goes.
Report a problem with this questionWhich handling characteristics are named for doubles and triples?
Answer: Off-tracking, response to steering, sensory feedback, braking, oscillatory sway, rollover in steady turns, and yaw stability in steady turns
Those characteristics are listed together in the handling item.
Report a problem with this questionIs off-tracking one of the handling topics a doubles/triples applicant must know?
Answer: Yes
Off-tracking is the first handling characteristic in the list.
Report a problem with this questionIs oscillatory sway a required doubles/triples knowledge topic?
Answer: Yes
Oscillatory sway is named with the other stability characteristics.
Report a problem with this questionWhich turn condition is named for rollover knowledge?
Answer: Rollover in steady turns
The handling list names rollover in steady turns and yaw stability in steady turns.
Report a problem with this questionIs yaw stability in steady turns part of the doubles/triples knowledge requirement?
Answer: Yes
Yaw stability in steady turns is named beside rollover in steady turns.
Report a problem with this question
Sources and study scope
The bank uses original questions based on federal rules and FMCSA material. The questions use the 2025 annual CFR edition, with selected current eCFR references checked on October 28, 2026. It is not a complete review of every later amendment. Each explanation links to its federal source. State manuals are further-study links; no AAMVA manual text is reproduced.
The 80% knowledge-test pass standard comes from 49 CFR 383.135. This site’s practice pool and session lengths do not determine your state’s official test format.