CDL General Knowledge TestCombination Vehicles (if applicable)Easy
When backing a combination vehicle, what is the primary reason to use your mirrors frequently and make small steering corrections?
- ATo monitor the air pressure in the trailer brake system.
- BTo ensure the trailer tires do not rub against the tractor tires.
- CTo prevent jackknifing and maintain control of the trailer's direction.
- DTo avoid hitting overhead obstructions with the trailer.
Show answer & explanationAnswer & explanation
Correct answer: C. To prevent jackknifing and maintain control of the trailer's direction.
Frequent mirror checks and small steering corrections are essential when backing a combination vehicle to keep the trailer aligned with the desired path and to prevent it from jackknifing, which can cause significant damage or injury.
Why the other options are wrong
- A. Air pressure is monitored via gauges, not primarily through mirror use during backing.
- B. While important, this is not the primary reason for frequent mirror checks during backing.
- D. Overhead obstructions are typically checked before backing begins, not continuously with mirrors during the maneuver.
Backing Combination Vehicles
Backing a combination vehicle requires constant vigilance using mirrors and making small, timely steering adjustments to prevent jackknifing.
- Jackknifing is a major risk.
- Small corrections are key.
- Mirrors are essential tools.
Memory trick: Small turns, big views, no jackknife blues.