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35 multiple-choice questions and 13 flashcards on General Knowledge — Vehicle Inspection, about 12% of the CDL Class A bank. Every one carries a written rationale.
General Knowledge — Vehicle Inspection is one of 12 chapters in CoStudy's CDL Class A (General Knowledge) bank, and it holds 35 of the bank's 300 multiple-choice questions — roughly 12% of the total. That proportion is not arbitrary: chapters follow the certifying body's published exam outline, and the number of questions in each is set by that domain's published weight, so the share of your practice time this chapter takes matches the share of the real exam it accounts for.
Studying by chapter is worth doing once you have a diagnostic score. A single overall percentage tells you whether you are close; it does not tell you which domain is dragging. Working a weak chapter in isolation, and re-testing it in isolation, is the fastest way to move a score that has stalled — and it is why the mock exams in CoStudy report by domain rather than as one number.
10 questions drawn from this chapter, with the full rationale shown — the controlling principle behind the right answer, and why each wrong option tempts and fails.
While checking the suspension a driver notices one leaf in a spring assembly has shifted out of position. Why does this matter MOST?
Answer: D — A shifted leaf can contact the tire or brake line and can lead to axle misalignment
D) Correct — a displaced leaf can strike the tire or air line and lets the axle wander, which is why broken or shifted spring leaves are treated as serious. B) Fuel use may change slightly, but that is not the safety reason the defect is called out. C) The suspension has no bearing on air pressure sensing; this mixes two unrelated systems. A) Rated capacity is set by the manufacturer and is not lowered by a defect; the defect simply makes the vehicle unsafe.
Which of the following is checked LAST in the standard 7-step pre-trip inspection?
Answer: D — Final brake check before pulling out
A) Step 1. B) Step 2. C) Step 3. D) Correct — the brake check (with vehicle in gear/release) is the final step before moving. Trap: many drivers skip this thinking the in-cab gauge check sufficed.
Lights and reflectors that you must inspect include:
Answer: D — Headlights, turn signals, brake lights, marker/clearance, reflectors, and tail lights
A/C/B) Incomplete. D) Correct — all required lights and reflectors must be inspected regardless of trip time, since trip may extend.
Minimum tire tread depth for STEERING tires?
Answer: C — 4/32 inch
A) That's the minimum for non-steering tires. B) Not a standard. C) Correct — steering tires require 4/32 inch (stricter than other tires). D) Exceeds federal minimum.
When checking the steering wheel for play, free play should not exceed approximately:
Answer: A — 10 degrees (about 2 inches on a 20-inch wheel)
A) Correct — about 10 degrees of free play is the limit; more indicates worn linkage. B/C/D) Excessive play indicates dangerous wear in steering components.
A driver is one hour into a long run. What does the en-route inspection duty MOST require?
Answer: A — Watching gauges and checking critical items at each stop and periodically along the route
A) Correct — en-route checks mean monitoring instruments and mirrors while driving and checking tires, brakes, cargo and lights when you stop. B) A full seven-step repeat at every stop is not required and is not what the rule contemplates. C) Written reports belong to the end of the driving day, not to each stop. D) Cargo checks matter, but tires, brakes and lights are also part of the en-route look.
During the post-trip inspection, you must:
Answer: D — Complete a Driver Vehicle Inspection Report (DVIR) when defects affect safety
A) Inspection itself is required; DVIR is conditional. D) Correct — current FMCSA rule: DVIR required only when defects/deficiencies are found that affect safety. C) Outdated — rule changed in 2014. B) Not required for the report itself.
An inspector examines a tractor and finds a brake drum with a crack extending through to the friction surface. What is the MOST likely result?
Answer: A — The vehicle is placed out of service until the drum is replaced
A) Correct — a cracked drum that reaches the friction surface can fail under heat and load, and it is a condition that stops the vehicle where it sits. B) A repair window applies to some paperwork and minor equipment items, not to a structural brake component. C) Recording and rolling on is what a non-critical defect allows; a compromised drum is not in that group. D) Deliberately taking an axle out of the braking system reduces braking capacity and is not a lawful workaround.
Coupling devices (fifth wheel) must be checked for:
Answer: D — Cracks, missing parts, secure mounting, and proper locking
A) Cosmetic only. D) Correct — inspect fifth wheel for cracks, missing/damaged parts, secure mounting bolts, and that jaws are locked around kingpin. C) Partial. B) Unrelated to coupling.
At the end of the day a driver completes a vehicle inspection report listing a defective marker lamp. Which statement about that report is correct?
Answer: B — The carrier must repair the defect and certify the repair before the vehicle is dispatched again
B) Correct — a defect noted on the report must be repaired or certified as not needing repair, and the next driver must review that certification. A) A verbal report leaves no record for the next driver and does not satisfy the written requirement. C) The following driver must review the report and sign only after seeing the certification, so blind sign-off defeats its purpose. D) The report is filed at the end of each driving day regardless of the driver's personal judgment about severity.
4 cards from the 13 in this chapter.
What is 'out of service'?
Roadside inspection order forcing immediate stop. Cannot resume until violation corrected.
What tire tread depth makes a vehicle unsafe and subject to out-of-service placement?
Less than 4/32 inch tread groove depth on any steer-axle tire, and less than 2/32 inch on all other tires.
How often must a driver stop to examine cargo and its securement on a long trip?
Within the first 50 miles after beginning a trip, then at each change of duty status, after driving 3 hours, or after driving 150 miles — whichever comes first.
Pre-trip inspection purpose?
Find problems that could cause crashes/breakdowns BEFORE driving.
These are a sample. The full General Knowledge — Vehicle Inspection chapter runs 48 items with per-chapter progress tracking, on the web and in the iOS app.