Practice Test Geeks(CDT) Certified Driver Trainer Practice Test
← All CDT Flashcard Decks

Vehicle Operations & Maintenance Flashcards

7 cards from real CDT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Vehicle Operations & Maintenance flashcards as text

  1. How does retarder use affect stopping distance on a wet or icy road?

    Answer: It can cause rear wheels to skid if used on slippery surfaces

    On slippery roads, engine or exhaust retarders can cause drive wheels to lock and skid because the retarding force exceeds available traction.

  2. What is the function of the glad hands on a tractor-trailer?

    Answer: Air line couplings that connect the tractor's brake air supply to the trailer

    Glad hands are the air line couplings (service and emergency) connecting the tractor's air supply to the trailer's brake system.

  3. When inspecting tires, a driver finds one tire in a dual set has significantly lower pressure than its pair. What should the driver do?

    Answer: Remove from service — a flat in a dual causes uneven load and bearing damage

    A significantly underinflated tire in a dual set should be treated as a flat; continuing to drive causes the overloaded companion tire to overheat and potentially fail.

  4. What does the 'override' position on a trailer air supply valve (tractor protection valve) allow?

    Answer: It keeps the trailer air supply open even if pressure drops below the normal cutoff

    The override position on some tractor protection valves allows the driver to keep the trailer connected to tractor air supply even when pressure falls below the automatic cutoff point.

  5. A CDL driver-trainer is teaching a student to shift a 10-speed manual transmission. At what point should the student begin moving the gear shift?

    Answer: When engine RPM drops to the target range for the next gear

    Proper shifting technique requires waiting until engine RPM drops to the correct range for the next gear before completing the shift to synchronize speeds.

  6. Which of the following is an indicator that wheel bearing failure may be imminent?

    Answer: Unusual heat from the hub area and a grinding noise during operation

    Excessive heat from the wheel hub area combined with grinding noises strongly indicates bearing failure and requires immediate inspection before the wheel separates.

  7. What is the maximum allowable brake lining thickness before replacement is required on a front steering axle?

    Answer: 1/4 inch

    FMCSA regulations specify that brake lining on steering axles must be replaced when worn to 1/4 inch (non-disc) to maintain safe braking performance.