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CDL Combination Vehicles Endorsement practice test

This free CDL combination vehicles endorsement practice test covers the knowledge test you take on top of your CDL, with original questions written from the federal knowledge requirements in 49 CFR Part 383.

  • Multiple-choice knowledge test
  • 80% to pass (49 CFR 383.135)
  • item count set by your state
Start 20 free questions What’s inside
  • No signup to start
  • Every answer includes a source note
  • Updated October 22, 2026

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Driving & Licenses · Exam prep

CDL Combination Vehicles Endorsement practice test: how the exam works and how to prepare

Original practice questions on the combination vehicles endorsement, written from the federal knowledge requirements in 49 CFR Part 383 and the public CDL manual facts; not official state test questions. The real CDL Combination Vehicles Endorsement test at a glance: Multiple-choice knowledge test, 80% to pass (49 CFR 383.135), item count set by your state. Use these free CDL Combination Vehicles Endorsement practice questions to learn the format and read the explanation and source note behind every answer.

80% is the federal threshold in 49 CFR 383.135. The regulation sets the percentage only — your state driver licensing agency sets how many questions the test has.

  • Learn the combination vehicles topics in the order your state manual teaches them
  • Use the free 20 first, then work the full bank by topic and retest what you missed
  • Read every explanation, including why the wrong options fail
  • Check your state's CDL manual for local numbers and rules before test day
Official format

The real test at a glance

What it takes to pass the CDL Combination Vehicles Endorsement test

80% to pass · question count set by your state

Quick Summary: The official CDL Combination Vehicles Endorsement knowledge test requires a minimum passing score of 80%. Format: Multiple-choice knowledge test. Sourced directly from official state testing blueprints.
  • Multiple-choice knowledge test
  • 80% to pass (49 CFR 383.135)
  • item count set by your state

80% is the federal threshold in 49 CFR 383.135. The regulation sets the percentage only — your state driver licensing agency sets how many questions the test has.

100
practice questions
20
free, no signup
80%
published threshold
50
questions per simulation

Topic coverage

Topics covered in this bank

100 original questions mapped to the listed source topics. Bars show how many questions each topic gets.

Original practice questions on the combination vehicles endorsement, written from the federal knowledge requirements in 49 CFR Part 383 and the public CDL manual facts; not official state test questions.

View full topic blueprint & drills →

Drill down by official testing module:

Driving rollover15Coupling15Combination air brakes15Inspecting15Off tracking swing10Backing trailer10

From the question bank

Try 3 more real questions

Answer in your head, then check. Every explanation cites the official source.

  1. Q1Driving rollover

    Which crash type accounts for more than half of truck driver deaths in crashes, according to the manual?

    1. ARear-end collisions with passenger cars
    2. BTruck rollovers
    3. CHead-on collisions at railroad crossings
    4. DCollisions with fixed objects at night
    Show answer

    B. Truck rollovers The manual says more than half of truck driver crash deaths come from rollovers. Piling more cargo up in a truck raises its centre of gravity, and that makes it easier to turn over. Rear-end crashes, head-on railroad collisions and fixed-object crashes are real risks, but the manual singles out rollovers as the main cause of truck driver deaths.

  2. Q2Driving rollover

    Which two actions does the manual name as helping to prevent a rollover?

    1. AFill the fuel tanks completely and avoid using the trailer hand valve
    2. BKeep the load toward one side and speed up through curves
    3. CKeep cargo close to the ground and drive slowly around turns
    4. DRaise the landing gear fully and brake only with the engine
    Show answer

    C. Keep cargo close to the ground and drive slowly around turns Low cargo keeps the centre of gravity down, and a lower speed in turns reduces the sideways force on the rig. Both reduce the chance of tipping. Filling the tanks, loading to one side, speeding through curves or braking only with the engine do nothing to keep the load low or slow the rig in turns.

  3. Q3Driving rollover

    What following distance does the manual give for a combination vehicle at speeds up to 40 mph?

    1. AAt least one second for each 40 feet of vehicle length
    2. BAt least two seconds no matter how long the vehicle is
    3. CAt least one second for each 10 feet of vehicle length
    4. DAt least one car length for each 10 mph
    Show answer

    C. At least one second for each 10 feet of vehicle length The manual's rule is at least one second for each 10 feet of vehicle length, with one more second added when you go faster than 40 mph. Forty feet per second, a flat two seconds or a car length per 10 mph ignore how much longer a rig is than a car and so give too little room.

All 20 free questions with answers Take them as a timed quiz

Study plan

How to pass the CDL Combination Vehicles Endorsement

The order that works: learn the rules, drill until they’re automatic, then use the exam simulator to check consistency.

  1. 1

    Learn the combination vehicles topics in the order your state manual teaches them

  2. 2

    Use the free 20 first, then work the full bank by topic and retest what you missed

  3. 3

    Read every explanation, including why the wrong options fail

  4. 4

    Check your state's CDL manual for local numbers and rules before test day

Exam simulator

Sit a timed mock test for the Combination

One question at a time against a real countdown, no feedback until you submit, flag questions to come back to, then a score against the pass mark with a by-topic breakdown and every answer explained. Topics are mixed across the whole bank, and a retake is a new draw.

Try the free mock test

The free mock test runs 20 questions from the free set, once. Unlocking adds full-length runs of 50 questions from the whole bank. A practice mock test, not an official replica.

Free taster
20 q
Full run
50 q
Practice clock
50 min
Pass mark
80%

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  • All 100 questions, every topic
  • 50-question timed exam simulator; see the score note below
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80% is the federal threshold in 49 CFR 383.135. The regulation sets the percentage only — your state driver licensing agency sets how many questions the test has.

Free study kit

Everything free for the CDL Combination Vehicles Endorsement test

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About these questions

Written by QuizCram from the official source and verified against its text — never copied from a real exam. Original practice questions on the combination vehicles endorsement, written from the federal knowledge requirements in 49 CFR Part 383 and the public CDL manual facts; not official state test questions.

Questions last updated
October 22, 2026
Bank version
v1 · 100 questions

Good to know

CDL Combination Vehicles Endorsement FAQ

Federal rules set the 80% passing threshold but not a question count. Each state writes its own test, so confirm the number with your state agency.

No. These are original practice questions on the combination vehicles endorsement. Your state licensing agency writes and scores the real test, and its CDL manual is the final word on local rules.

Yes. Open the exam simulator and sit a timed mock test of 20 questions built from the free questions, once, with no signup. Unlocking the exam adds full-length runs of 50 questions in 50 minutes (a practice clock), as many as you like, each a new draw from the whole bank.

The exam's agency publishes no topic weights, so it mixes topics in proportion to the question bank, favouring questions you missed before and never repeating one within a run. A retake is a new draw, so you will meet different questions. It is a practice mock test, not an official replica of the real exam.

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