Oklahoma SOK CDL General Knowledge Practice Test 1
Test 1 of 5. Pick an answer for each question to see if it is right and why; your score appears at the end. You need 40 correct answers to pass, the same ratio as the real Oklahoma test.
- Questions50
- Correct to pass40
- Passing score80%
- Minimum age18 years
-
1. Oklahoma's ban on hand-held phone calls for public transit drivers reaches which additional operator, beyond bus and transit vehicle drivers?
Show answer
Answer C: Operators, conductors or drivers of a locomotive engine, railway car or train
Oklahoma's statutory definition of public transit driver, for purposes of the hand-held phone ban, extends to any operator, conductor or driver of a locomotive engine, railway car or train of cars.
-
2. What does the working load limit stamped on a chain or strap describe?
Show answer
Answer B: The maximum load the device is rated to hold in normal use
The working load limit is the rated safe capacity for everyday use, deliberately set well below the force that would break the device.
-
3. On the Interstate System, what are the federal maximums for a tandem axle group and for gross vehicle weight?
Show answer
Answer B: 34,000 pounds and 80,000 pounds
The federal Interstate limits allow 34,000 pounds on a tandem axle group and 80,000 pounds gross.
-
4. Under federal rules, which commercial vehicles must stop at every railroad crossing before proceeding?
Show answer
Answer D: Passenger buses and placarded hazardous materials vehicles
Buses carrying passengers and vehicles required to display hazardous materials placards must stop at crossings, while other commercial vehicles slow and check.
-
5. A driver snores heavily, stops breathing briefly during the night and is tired all day despite long hours in bed. What should be suspected?
Show answer
Answer B: Sleep apnea
Sleep apnea repeatedly interrupts breathing during sleep, so the driver never gets true rest and stays dangerously drowsy during the day.
-
6. You have a part load that fills only a third of a long trailer. How should it be placed?
Show answer
Answer C: Spread out and centerd side to side, so the weight sits over the axles
A part load is spread over as much of the floor as possible and kept centerd, so no axle is overloaded and the vehicle stays balanced from side to side.
-
7. What condition should the fifth wheel be in before you back under a trailer?
Show answer
Answer C: Jaws open, plate greased, and the fifth wheel tilted down toward the rear
The jaws have to be open to take the kingpin, the plate must be lubricated to prevent hard steering, and the fifth wheel is tilted down at the rear so the trailer apron can ride up onto it.
-
8. What speed and gear should be used when backing a large vehicle?
Show answer
Answer B: As slowly as possible, in the lowest reverse gear
Backing slowly in the lowest reverse gear keeps the vehicle under precise control and leaves time to correct the path.
-
9. Who may remove an out-of-service sticker from a commercial vehicle?
Show answer
Answer B: Only an authorized person, and only after the defect that caused it has been repaired
The sticker stays on the vehicle until the repairs are made and an authorized person removes it, so nobody can simply peel it off and drive away.
-
10. Why is a leaking exhaust system on a commercial vehicle dangerous to the driver?
Show answer
Answer B: It can let carbon monoxide reach the cab, where it can poison the occupants
Exhaust gas contains carbon monoxide, which has no smell and dulls the driver judgment long before it becomes obvious that anything is wrong.
-
11. You drop your phone on the floor of the cab while driving. What do federal rules require?
Show answer
Answer A: Leave it, because reaching for it while driving is banned
Federal rules forbid reaching for a mobile device in any way that takes the driver out of a seated, belted driving position.
-
12. What is the driver responsible for when a load is covered with a tarp?
Show answer
Answer C: Fastening it so it cannot flap free, block a mirror, or come off in the wind
A tarp that works loose can tear away, block the driver view or the view of others, and become a hazard for the traffic behind.
-
13. When does Oklahoma require the N tank vehicle endorsement?
Show answer
Answer C: For tanks with an individual capacity of more than 119 gallons and an aggregate capacity of 1,000 gallons or more
The Oklahoma N endorsement covers commercial vehicles designed to transport liquids or gases in tanks with an individual rated capacity of more than 119 gallons and an aggregate rated capacity of 1,000 gallons or more.
-
14. A driver behind you wants to pass and you can see that the road ahead is clear. What should you do?
Show answer
Answer B: Do not signal the other driver to pass; let that driver decide when it is safe
Directing other drivers can cause a crash if you misjudge the gap, so leave the decision to the driver who is passing.
-
15. What is the most common cause of a front-wheel skid, where the vehicle keeps going straight even though you turn the wheel?
Show answer
Answer B: Driving too fast for the conditions
A front-wheel skid usually comes from too much speed for the traction available; the only cure is to let the vehicle slow down and stop turning or braking so hard.
-
16. Why does a load of live animals need special attention?
Show answer
Answer D: The animals move and lean, so the center of gravity shifts and the vehicle can be pushed off balance in a turn
A live load will not stay where it is put, and that movement changes the balance of the vehicle exactly when a curve is loading it most.
-
17. Within what distance should high beams be lowered at night?
Show answer
Answer D: Within about 500 feet of an oncoming vehicle and within about 500 feet of a vehicle you are following
High beams blind other drivers at close range, so they are lowered at roughly the same distance whether the other vehicle is coming toward you or is ahead of you.
-
18. What does a front-end header board on a van or flatbed protect against?
Show answer
Answer A: Cargo moving forward toward the cab in a crash or hard stop
The header board, often called a headache rack, blocks forward movement of the load toward the driver.
-
19. A company mechanic serviced your truck this morning and signed the work order. Do you still have to inspect the vehicle?
Show answer
Answer B: Yes, the driver is still responsible for being satisfied the vehicle is safe
Shop work does not transfer the duty; the driver who takes the vehicle out remains responsible for being satisfied it is in safe operating condition.
-
20. After coupling, where should the fifth wheel release handle be?
Show answer
Answer A: In the locked position with the safety latch in place
The handle must be pushed in and latched, because a handle left out means the jaws can open and release the trailer while you are driving.
-
21. Why should you never shift gears while crossing railroad tracks?
Show answer
Answer A: You could miss the gear or stall and be stuck on the tracks
A stalled or coasting vehicle on the tracks has no way to clear quickly, so choose the gear before the crossing and do not shift until you are across.
-
22. A fire has started in the vehicle. How should the extinguisher be used?
Show answer
Answer B: Stay as far back as the reach of the extinguisher allows, stand upwind, and aim at the base of the fire
Aiming at the base attacks what is actually burning, and staying upwind and well back protects the driver from heat, smoke and the flames themselves.
-
23. What is the fine for a commercial or public transit driver convicted of using a hand-held cellular telephone while operating a vehicle in Oklahoma?
Show answer
Answer A: $500
Oklahoma's statute on unlawful use of a cellular telephone by commercial and public transit drivers sets a $500 misdemeanor fine, five times the fine for the general texting ban.
-
24. What do you check about the fire extinguisher during the pre-trip?
Show answer
Answer C: That it is securely mounted, charged and that you know how to operate it
An extinguisher must be held in its bracket, show a charged gauge and be understood by the driver, because a fire leaves no time to learn.
-
25. A tire blows out at highway speed. What should the driver do first?
Show answer
Answer C: Hold the steering wheel firmly, stay off the brake and let the vehicle slow down
Braking while a tire is gone can pull the vehicle out of line, so the driver keeps it straight and lets speed fall before easing off the road.
-
26. How do you get more engine braking from an automatic transmission on a downgrade?
Show answer
Answer B: Select a lower range before starting down
Locking the transmission into a lower range keeps engine speed high enough to hold the vehicle back and spares the service brakes.
-
27. You must steer hard around an obstacle at highway speed. What is the correct technique?
Show answer
Answer B: Avoid braking while turning, turn only as far as needed, and countersteer as soon as the obstacle is passed
Braking during a hard steering input can lock the wheels and start a skid, and turning back at once keeps the vehicle from running off the far side of the road.
-
28. Which vehicle is most likely to be pushed around by a strong crosswind?
Show answer
Answer B: An empty van trailer
A large flat side with very little weight behind it gives the wind the most surface and the least resistance, which is the empty van trailer.
-
29. What must be checked on a sliding fifth wheel during the inspection?
Show answer
Answer B: That it is locked in position and not so far forward that the trailer can hit the cab
A slider that is unlocked can move under braking, and one set too far forward lets the trailer strike the cab when the tractor turns sharply.
-
30. Why must the downshift be finished before you reach a steep downgrade or a sharp curve rather than during it?
Show answer
Answer D: Because once your speed is too high you may not get into any gear at all
If you wait until speed has built up, the lower gear may refuse to engage and you can be left in neutral with no engine braking at all.
-
31. You have backed into the same loading bay every week for a year. How often should you still get out and walk to the rear before backing?
Show answer
Answer D: Every time, since the area can change while you are away from it
A familiar space is no guarantee; vehicles, pallets, people and overhead obstructions appear between one visit and the next, so you check on every occasion.
-
32. During uncoupling, when may the fifth wheel locking lever be released?
Show answer
Answer D: Only after the landing gear is down and taking the weight of the trailer
The landing gear has to be supporting the trailer before the lock is released; otherwise the trailer nose can drop as soon as the tractor pulls out.
-
33. Which components on a typical engine are driven by belts that must be checked for wear and tension?
Show answer
Answer D: The alternator, the water pump and, on many vehicles, the air compressor
Belts drive accessories such as the alternator, the water pump and the air compressor, so one failed belt can take out charging, cooling or air supply.
-
34. After starting the engine, how quickly should the oil pressure gauge come up to its normal range?
Show answer
Answer B: Within a few seconds
Oil pressure should build within seconds of starting; if it stays low, the engine is not being lubricated and should be shut down.
-
35. What is generally the safest speed in dense but freely moving highway traffic?
Show answer
Answer D: The speed of the traffic around you, up to the posted limit
Crashes rise with the difference between your speed and the traffic around you, so moving with the flow within the legal limit is safest.
-
36. What does the tachometer on the dashboard of a heavy truck show?
Show answer
Answer D: How fast the engine is turning, in revolutions per minute
The tachometer reads engine speed in rpm, which is what a driver uses to judge shift points in a vehicle with a manual transmission.
-
37. On packed snow, how much should a commercial driver reduce speed?
Show answer
Answer D: By about one half or more
Packed snow costs far more traction than rain, so speed should be cut by half or more.
-
38. Which of these is a suspension defect you must look for during the walkaround?
Show answer
Answer D: Cracked or broken spring leaves, loose or broken U-bolts, or leaking air suspension bags
Broken springs, failed U-bolts and leaking air bags let the axle shift or the body drop, which can make the vehicle impossible to control.
-
39. You are backing a tractor-trailer in a straight line and the trailer starts to drift to the left. What is the standard correction?
Show answer
Answer D: Turn the top of the steering wheel a little to the left, toward the drift
Small corrections made in the direction the trailer is drifting bring it back into line; large or opposite movements make the drift worse.
-
40. What is required of the hooks, rails, rings and anchor points that tiedowns attach to?
Show answer
Answer A: They must be part of the vehicle and strong enough for the load being secured
A tiedown is only as strong as what it is hooked to, so anchor points must be proper vehicle fittings rated for the job.
-
41. What do the U-bolts on a leaf spring suspension do?
Show answer
Answer A: They clamp the spring assembly to the axle so it cannot move
U-bolts hold the spring pack tight against the axle, and a loose or broken U-bolt lets the axle slide out of place under load.
-
42. How much sleep does a typical adult driver need each day to stay properly alert?
Show answer
Answer D: Seven to eight hours
Most adults need seven to eight hours of sleep in every 24 hours, and a driver who regularly gets less builds up a debt that shows up behind the wheel.
-
43. At a rest area you find that the load has shifted although the straps still feel tight. What should you do?
Show answer
Answer C: Correct the load before driving on, since a shifted load is no longer secure
Movement means the securement has already failed once, and a load that has shifted can shift again, so it is put right before the vehicle moves.
-
44. During a stop you find a package in the trailer leaking an unknown chemical. What should you do?
Show answer
Answer C: Keep clear, keep others away and get help without touching the package
A driver without the training and equipment does not handle a leak; the job is to protect people from the material and get qualified help to the scene.
-
45. You are the first to arrive at a crash. What is the correct order of actions?
Show answer
Answer C: Protect the area, notify the authorities, care for the injured
Preventing a second crash comes first, because an unprotected scene puts the injured and the helpers in more danger than the original collision.
-
46. What does mountain driving demand that flat country driving does not?
Show answer
Answer D: Lower gears and constant allowance for gravity
In the mountains gravity works for you on the climb and against you on the descent, so gear selection and speed control matter far more than on level road.
-
47. The temperature is around freezing and the road looks wet. What is a practical way to tell whether it is icy?
Show answer
Answer C: Check for ice building up on the mirrors, antenna or the front of the vehicle
Ice that forms on the mirror, antenna or windshield is a warning that the road surface is freezing too, and black ice can look like a wet road.
-
48. Before raising the hood to inspect the engine compartment, what should you do?
Show answer
Answer B: Shut off the engine, set the parking brake and chock the wheels if needed
The engine compartment is inspected with the engine off and the vehicle secured so nothing can move or turn while your hands are inside.
-
49. Which wheel or rim condition must be treated as a defect during the walkaround?
Show answer
Answer C: Cracks, illegal welded repairs, or missing and loose lug nuts
Cracked or welded rims and missing or loose fasteners can let a wheel separate from the vehicle and must be corrected before driving.
-
50. What information does an inspection decal on a commercial vehicle carry?
Show answer
Answer B: The date of the inspection, where the inspection report is kept, and information identifying the vehicle
The decal shows when the inspection was done, the name and address of the entity that holds the inspection report, and which vehicle it belongs to, so an officer can confirm the inspection at a glance.