TheoryCDL Commercial License Prep Practice Test Video
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CDL Commercial License Prep exam — full Q&A walkthrough
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Q1During a pre-trip inspection, which tire condition would most likely cause a vehicle to be placed out of service?
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✓ Correct answer: Tread depth below 2/32 inch on steering tires
Tread depth below 2/32 inch on steering tires is a critical safety violation that would place a commercial vehicle out of service, as it significantly increases the risk of blowouts and loss of vehicle control.
Q2What is the proper method for checking brake adjustment on a commercial vehicle?
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✓ Correct answer: Measure the pushrod travel when brakes are applied
The correct method for checking brake adjustment is to measure the pushrod travel when brakes are applied, which determines if the brakes are properly adjusted for optimal stopping performance.
Q3Which of the following is NOT a required item to check during a steering component inspection?
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✓ Correct answer: Navigation system functionality
While steering components must be thoroughly inspected, the vehicle's navigation system is not part of the required steering component inspection as it doesn't affect the mechanical operation of the steering system.
Q4When inspecting air brake slack adjusters, what is the maximum allowable free play for most commercial vehicles?
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✓ Correct answer: 1/4 inch
The maximum allowable free play for most commercial vehicle slack adjusters is 1/4 inch, beyond which brake performance would be compromised and could result in an out-of-service violation.
Q5Which emergency equipment item is NOT typically required to be carried on a commercial motor vehicle?
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✓ Correct answer: First aid kit
While fire extinguishers, warning triangles, and spare fuses are required emergency equipment items, a first aid kit is not federally mandated equipment for all commercial motor vehicles (though it is recommended).
Q6What condition would make headlights fail inspection?
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✓ Correct answer: Different colored headlights
Different colored headlights would fail inspection as they violate regulations requiring matched, properly colored lights for visibility and to avoid confusing other drivers.
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