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Combination Vehicles Practice Question 1

Required for Class ACombination Vehicles · Question 1

A combination vehicle is generally defined as:

• AAny truck over 26,001 lb GVWR
• BA power unit pulling a trailer over 10,000 lb GVWR with combined GVWR over 26,001 lb
• CA bobtail tractor
• DA vehicle with three axles

Correct answer: B. A power unit pulling a trailer over 10,000 lb GVWR with combined GVWR over 26,001 lb

Why: Class A CDL covers combination vehicles where the combined GVWR exceeds 26,001 pounds and the trailer alone is over 10,000 pounds.

How this question fits the Combination test

Articulated vehicles fail in unique ways: trailer swing under braking, rearward amplification under steering, and jackknife under loss of traction. Combination Vehicle knowledge is required for any Class A applicant under 49 CFR 383.111.

Study technique for this topic

Walk through the coupling sequence verbally until it's second nature. Know the safe-rolling rearward amplification factor, the difference between trailer service brakes and parking brakes, and what creates the conditions for a tractor jackknife.

Related Combination practice questions

• Q40. When approaching an intersection in a combination vehicle, you should:
• Q53. The blind spots of a tractor-trailer include:
• Q3. The kingpin is part of the:
• Q16. A loaded trailer with a high center of gravity is most prone to roll over:
• Q29. A leaky air line between tractor and trailer will most likely cause:

Continue your CDL preparation

The Combination Vehicles portion of the CDL knowledge exam covers more than this single question. Use this site's full Combination Vehicles bank to drill every topic, then test yourself with one of our state-specific practice sets to confirm you are ready for the actual DMV exam in your state. Always check your state's CDL handbook for any local addenda before the test day.

If you are still building your overall CDL foundation, start with the General Knowledge bank — every CDL applicant must pass it — and then work outward to the endorsements you plan to add.