Kentucky CDL: General Knowledge Practice Test

Not quite. The answer is All of the above

The amount of off-tracking depends on three factors: the length of the vehicle, the sharpness of the curve or turn, and the amount of sideways drag on the rear tires. In general, the longer the vehicle, the greater the off-tracking. In a tractor-trailer, the amount of off-tracking depends on both the distance from the steering axle to the trailer kingpin, and the distance from the trailer kingpin to the trailer rear wheels. If your trailer is equipped with sliding tandems, then sliding the tandems backward will increase off-tracking. Also, the sharper the curve or turn, the greater the off-tracking. And the stronger the sideways drag on the rear tires, the greater the off-tracking.

Not quite. The answer is at all times.

Regardless of whether you're a passenger or the driver, you should wear your seatbelt at all times while the vehicle is moving. Seatbelts are proven to save lives and reduce injuries. Federal regulations require the driver and all passengers who are seated in a moving commercial motor vehicle (CMV) to wear seatbelts (unless, of course, the seats aren't equipped with them).

Source: 49 CFR 392.16

Not quite. The answer is 2 holes forward

Under federal regulations, the maximum gross vehicle weight (GVW) is 80,000 pounds, the maximum gross weight on the drive axles is 34,000 pounds, and the maximum gross weight on the tandem axles is also 34,000 pounds. This leaves 12,000 pounds on the steering axle. In this case, the steering axle is quite underweight (by 1,100 pounds), and the drive axles are overweight by 600 pounds. The weight on the steering axle should be close to 12,000 pounds without exceeding it. To better balance the weight on the tractor, we need to move some weight off the drive axles and put it on the steering axle. To add weight to the steering axle and remove weight from the drive axles, move the fifth wheel forward (toward the steering axle). Assuming 500 pounds per hole, moving two holes will move 1,000 pounds from the drive axle to the steering axle. The resulting weights are 11,900 pounds on the steering axle and 33,600 pounds on the drive axles.

Source: 23 CFR 658.17

Not quite. The answer is restore traction to the tires.

If braking or steering force exceeds the tires' traction with the road surface, a skid may result. You can recover from the skid by restoring sufficient traction.

Not quite. The answer is Brush

In the wintertime, remove snow and ice from your windshield, windows, and mirrors before you drive. Your vehicle's defroster will help melt some ice and snow to the point that you can clear them more easily. Clear the ice with an ice scraper. A snow brush can clear snow but isn't designed to clear ice. However, some snow brushes come with an ice-scraper attachment at the other end.

Not quite. The answer is both of the above.

Regardless of who loads and secures the cargo, you, the driver, are responsible for its safety. As part of your pre-trip inspection, make sure that the cargo is balanced, secured, and not overloaded, and does not get in the way of emergency equipment. The cargo's safety could be compromised otherwise.

Not quite. The answer is 2 hours; 32 hours

Under federal regulation 49 CFR 382.303, if you've been notified to get alcohol and drug tested after a crash, you must submit the alcohol test to your employer within 2 hours of the notification and the drug test within 32 hours of the notification. It is your responsibility to get tested. If you're unavailable for testing, your employer may consider you as having refused testing, which can have serious consequences. Of course, you are legitimately unavailable if you're being treated for injuries you sustained in the crash, or you're helping to get medical assistance for others involved in the crash.

Not quite. The answer is 4/32 inch

Steering axle tires must have a tread depth of at least 4/32 inch. All other tires must have a tread depth of at least 2/32 inch.

Not quite. The answer is show a wider area than flat mirrors.

A convex mirror has a wider field of view than a flat mirror. However, objects viewed in a convex mirror look smaller and farther away than they really are. Bear this in mind when you're trying to judge the distance of an object that you're viewing in a convex mirror.

Not quite. The answer is Accelerating while pressing the clutch and turning toward the driver's side

You must release the accelerator, press the clutch and shift into neutral at the same time, release the clutch, let the engine and gears slow to the required rpm for the next gear, press the clutch and shift into a higher gear at the same time, then release the clutch and press the accelerator at the same time. Acceleration is not involved until the very end, and definitely not while pressing the clutch.

Not quite. The answer is Leave your high beams on.

To avoid blinding other drivers, dim your headlights whenever you're within 500 feet of an oncoming vehicle or within 500 feet of a vehicle you are following.

Not quite. The answer is Release the accelerator.

Hydroplaning is more likely at higher speeds. If your vehicle starts to hydroplane, avoid braking. Instead, release the accelerator and push in the clutch to let your vehicle slow down.

Not quite. The answer is both of the above.

Before driving your vehicle, adjust your mirrors to show parts of your vehicle as well as what's around your vehicle. During your trip, you can use your mirrors to keep an eye on your tires and open cargo if any. When merging, use your mirrors to make sure the gap in traffic is large enough for you to enter safely.

Not quite. The answer is All of the above

While the rules vary by jurisdiction, section 3.1 of the Kentucky CDL Manual states that you should check your cargo within the first 50 miles of your trip and then every 3 hours or 150 miles, as well as after each break you take.

Not quite. The answer is both of the above.

Overloading can adversely affect steering, braking, and speed control. Also, most states impose maximum weight limits on CMVs to prevent excessive weight from damaging roadways or bridges.

Not quite. The answer is Brake shoes should not be worn dangerously thin.

When you check your brakes during your pre-trip inspection, check that the brake shoes are all present and none are broken or worn dangerously thin.

Not quite. The answer is balanced in the cargo area.

Keep your load of cargo balanced. You need enough weight on both the steering and drive axles for adequate traction. However, too much weight on the steering axle can cause hard steering and even damage the steering axle and tires. Too much weight on one side can increase the risk that the cargo will shift.

Not quite. The answer is There may be strong winds when exiting.

Inside a tunnel, you don't feel the effect of crosswinds pushing you sideways. But once you emerge from the tunnel into an open space, the crosswinds will hit you. If your vehicle is traveling alongside another vehicle, there is some chance that the crosswinds will push one of the vehicles against the other.

Not quite. The answer is All of the above

Obstructive sleep apnea (OSA) can cause excessive daytime sleepiness and difficulty concentrating, which can impair your ability to drive a CMV safely. Risk factors for developing OSA include the male gender, obesity, smoking, and being age 40 or older. Many truck drivers have all these risk factors. A study sponsored by FMCSA found that 28% of commercial truck drivers have mild to severe sleep apnea. Fortunately, OSA is treatable.

Not quite. The answer is use the braking effect of the engine.

When you drive down long, steep downgrades, the braking effect of your engine is what's most important, and your service brakes are only a supplement to being in the proper low gear. They cannot compensate for your vehicle being in an unsafe high gear without putting too much pressure on your brakes. Save your brakes so you will be able to slow or stop as required by road and traffic conditions.