Oregon CDL — General Knowledge Practice Test
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Oregon CDL — General Knowledge questions with answers
20 sample questions from the Oregon CDL — General Knowledge question bank — each with the correct answer, a short explanation, and the section of the official handbook it comes from.
1. How do objects appear in a convex (fisheye) mirror compared to how they really are?
Correct answer: Smaller and farther away than they are
In a convex mirror everything looks smaller and appears farther away than it actually is.
Source: Oregon Commercial Driver Manual, Section 2.4.2 - Seeing to the Sides and Rear
2. After a tire has been changed, what should you do a short time later?
Correct answer: Stop soon and re-check the tightness of the nuts
After a tire has been changed, stop a short while later and re-check the tightness of the lug nuts.
Source: Oregon Commercial Driver Manual, Section 2.1.3 - What to Look For
3. What are the minimum age requirements for an Oregon CDL?
Correct answer: At least 18, and 21 for interstate commerce
You must be at least 18 to get an Oregon CDL and at least 21 to drive commercial vehicles in interstate commerce.
Source: Oregon Commercial Driver Manual, Section i - Oregon Information
4. Where do you place warning devices when stopped on a one-way or divided highway?
Correct answer: At 10, 100, and 200 feet toward approaching traffic
On a one-way or divided highway, place the devices 10 feet, 100 feet, and 200 feet toward the approaching traffic.
Source: Oregon Commercial Driver Manual, Section 2.5.2 - Communicating Your Presence
5. At what speed can hydroplaning begin when there is a lot of water on the road?
Correct answer: As low as 30 mph
Hydroplaning can occur at speeds as low as 30 mph when there is a lot of water on the road.
Source: Oregon Commercial Driver Manual, Section 2.6.2 - Matching Speed to the Road Surface
6. Why are drivers of delivery and step vans a special hazard?
Correct answer: They may suddenly step out or pull into traffic
Their vision is often blocked by packages, and they may suddenly step out or drive into the traffic lane.
Source: Oregon Commercial Driver Manual, Section 2.8.3 - Drivers Who Are Hazards
7. At a passive railroad crossing that has no traffic control device, who decides whether to stop or proceed?
Correct answer: The decision rests entirely with you
At a passive crossing there is no signal, so the decision to stop or proceed rests entirely with the driver.
Source: Oregon Commercial Driver Manual, Section 2.15.1 - Types of Crossings
8. If you must drive onto the shoulder to avoid a crash, when should you brake?
Correct answer: Wait until speed drops to about 20 mph, then brake gently
Avoid using the brakes until your speed has dropped to about 20 mph, then brake gently to avoid skidding on the loose surface.
Source: Oregon Commercial Driver Manual, Section 2.17.1 - Steering to Avoid a Crash
9. What is the only thing that will actually sober up a person who has been drinking?
Correct answer: Only the passage of time
The liver removes alcohol at a fixed rate, so only the passage of time will sober you up, not coffee or a cold shower.
Source: Oregon Commercial Driver Manual, Section 2.22.1 - Alcohol and Driving
10. What pavement markings warn of a railroad crossing on a two-lane road?
Correct answer: An X together with the letters RR painted on the pavement
The markings painted on the road are an X with the letters RR, along with a no-passing marking on two-lane roads.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
11. How much of your work history must you give an employer when applying for a commercial driving job?
Correct answer: Every driving job held during the previous 10 years
You must provide information on every driving job you have held during the previous 10 years.
Source: Oregon Commercial Driver Manual, Section 1.4 - Other CDL Rules
12. What color is the ABS malfunction lamp on a tractor's instrument panel?
Correct answer: Yellow
Tractors, trucks, and buses have yellow ABS malfunction lamps on the instrument panel.
Source: Oregon Commercial Driver Manual, Section 2.18.3 - How to Know If Equipped with ABS
13. Before starting across railroad tracks, what must you make sure of?
Correct answer: That you can clear the tracks completely before starting
Never permit traffic to trap you on the tracks; be sure you can get all the way across before you start.
Source: Oregon Commercial Driver Manual, Section 2.15.5 - Crossing the Tracks
14. For a first offense of driving a CMV with a BAC of .04 percent or higher, how long do you lose your CDL?
Correct answer: At least one year
You will lose your CDL for at least one year for a first offense such as driving a CMV with a BAC of .04 percent or higher.
Source: Oregon Commercial Driver Manual, Section 1.3.2 - Alcohol, Leaving the Scene, and Felony
15. Which lights should you use when driving very slowly or stopped in a spot where you may surprise traffic?
Correct answer: Your four-way emergency flashers
Use the four-way emergency flashers when you are driving very slowly or stopped to alert other drivers.
Source: Oregon Commercial Driver Manual, Section 2.5.1 - Signal Your Intentions
16. How does the following-distance rule change when you are driving faster than 40 mph?
Correct answer: Add one second
At speeds over 40 mph you must add one second to the following distance for safety.
Source: Oregon Commercial Driver Manual, Section 2.7.1 - Space Ahead
17. Why are children near the roadway considered a serious hazard?
Correct answer: They may dart out without looking for traffic
Children tend to act quickly without checking traffic and may dart into the road.
Source: Oregon Commercial Driver Manual, Section 2.8.3 - Drivers Who Are Hazards
18. Why must you look both ways before crossing a double set of railroad tracks?
Correct answer: One train can hide a second train on the other track
A train on one track can hide a train approaching on the other track, so you must check both directions.
Source: Oregon Commercial Driver Manual, Section 2.15.3 - Driving Procedures
19. When you leave the road onto the shoulder, what helps you keep control?
Correct answer: Keep one set of wheels on the pavement
Keep one set of wheels on the pavement, if possible, to help maintain control.
Source: Oregon Commercial Driver Manual, Section 2.17.1 - Steering to Avoid a Crash
20. How much alcohol can it take to show signs of impairment in some people?
Correct answer: As little as one drink
For some people, one drink is all it takes to show signs of impairment.
Source: Oregon Commercial Driver Manual, Section 2.22.1 - Alcohol and Driving