Delaware CDL: General Knowledge Practice Test

Not quite. The answer is death.

Under federal regulation 49 CFR 382.303, if you're involved in a crash, your employer must test you for drugs and alcohol if (a) there was a fatality, or (b) you received a citation under local or state law AND the crash involved an injured person being transported from the scene or a disabled vehicle being towed from the scene. If you were not cited, then you need not be tested as long as the crash didn't result in death.

Not quite. The answer is at least 419 feet.

At 55 mph under good driving conditions, your total stopping distance will be at least 419 feet: 142 feet of perception distance + 61 feet of reaction distance + 216 feet of braking distance. Under poor driving conditions, the total stopping distance will probably be even longer. (The length of a football field including the two end zones is 360 feet.)

Not quite. The answer is Chains

Under federal regulations, a "large boulder" has a volume of more than 2 cubic meters or weighs more than 11,000 pounds. Each large boulder must be supported on at least two pieces of hardwood blocking that extend across the full width and 3/4 of the length of the boulder. Only chains can be used as tie-downs. The chains should be placed in valleys or notches on the top of the boulder, and arranged to prevent the chains from sliding across the rock surface.

Source: 49 CFR 393.136

Not quite. The answer is Heavy vehicles need larger gaps in traffic than cars.

Large, heavy vehicles accelerate more slowly than passenger cars, and they are also longer. When driving such a vehicle, you need a much bigger gap to enter traffic than you would if you were driving a car.

Not quite. The answer is you can see better, watching the vehicle's rear from the side window.

You should always back toward the driver's side because you will be able to see things much more easily. For example, you can keep an eye on the vehicle's rear by viewing it from your side window. If your truck pulls in either direction, it needs service. Your neck's comfort should not affect your safety decision.

Not quite. The answer is Quieter operation

For large CMVs, diesel engines offer several advantages over gasoline engines. A diesel engine's high compression ratio gives it higher thermal efficiency, and therefore, about 25% greater fuel efficiency. Diesel engines produce a lot of power at low rpms. Diesel engines can last more than twice as long as gasoline engines (although this obviously depends on the specific models of engines). Finally, diesel fuel is safer than gasoline. Gasoline is highly flammable, and its vapors are highly explosive. Diesel fuel won't burn readily unless it's compressed (as in the cylinders of diesel engines). However, diesel engines are typically louder than gasoline engines.

Not quite. The answer is You may never park on the ramps.

Freeway and turnpike exits can be particularly dangerous for commercial vehicles. Off ramps and on ramps often have speed limit signs posted - these speeds may be safe for cars, but not for larger vehicles or heavily loaded vehicles. Exits that go downhill and turn at the same time can be especially dangerous. The downgrade makes it difficult to reduce speed. Braking and turning at the same time can be a dangerous practice. Make sure you are going slowly enough before you get on the curved part of an off ramp or on ramp. Do not park on the ramps.

Not quite. The answer is the tracks have a steep approach.

Raised railroad crossings with steep approaches can cause your vehicle to get hung up on the tracks. This is more likely if you're driving a vehicle with low ground clearance (such as a lowboy, car carrier, or moving van).

Not quite. The answer is all of the above.

You will lose your CDL for at least 60 days if you commit two serious traffic violations in a CMV within a three-year period. Some examples of serious traffic violations are excessive speeding (15 mph or more above the posted speed limit), reckless driving, erratic lane changes, and following too closely (tailgating).

Not quite. The answer is Stop driving as soon as you can safely do so.

When traveling on ice, your vehicle's braking distance can increase tremendously. On ice, slow down to a crawl and stop driving as soon as you can do so safely.

Not quite. The answer is Both of the above

To drive safely on snowy surfaces, your tires should be in the best possible shape. Consider exceeding the federal minimum requirements on tire tread depth (4/32 inch for front tires and 2/32 inch for the other tires). Make sure that your exhaust system has no leaks. An exhaust leak can allow dangerous fumes to enter your cab or sleeper berth. This can be especially dangerous in cold temperatures in which you will be more likely to keep the windows tightly shut.

Source: 49 CFR 570.62

Not quite. The answer is poor traction on the drive wheels.

When loading a semitrailer, make sure that the load is properly balanced. For example, insufficient weight on the tractor's drive axles (caused by placing the load too far to the rear) can cause poor traction and cause the drive wheels to spin more easily, especially on slippery roads.

Not quite. The answer is Driving too fast

More than half of truck driver deaths in crashes are the result of truck rollovers. Rollovers can happen when you turn too fast or drive through a curve too fast. If you drive through a curve too fast when poor weather has made the roadway slippery, your vehicle may slide off the road entirely, which can also result in a fatal accident.

Not quite. The answer is Both of the above

There are many things you must check during your pre-trip inspection. During Step 1 (Vehicle Overview) of the Seven-Step Inspection Method, check the condition of the windshield wipers. During Step 4 (Turn Off Engine and Check Lights) and Step 5 (Walk-Around Inspection), you'll check that the lights are working.

Not quite. The answer is 38,000 pounds

Federal regulations impose maximum weight limits on CMVs traveling on interstate highways. The maximum allowable Gross Combination Weight Rating (GCWR) is 80,000 pounds. The single axle weight rating is 20,000 pounds, and the tandem axle weight rating is 34,000 pounds for typical tandem axles that are spaced 40 to 96 inches apart, from center to center. For tandem axles spaced 97 inches apart, the axle weight rating is 38,000 pounds. The tridem axle, or three-axle, weight rating is 42,000 pounds if the outermost two axles are 97 inches apart.

Not quite. The answer is All of the above

In your logbook, you must record each change of duty status, accurate to the nearest quarter hour (15 minutes). For each change, enter the location of the change and the reason for it in the Remarks section. Federal regulations refer to this information as an annotation, and electronic logging devices (ELDs) should have a way to enter such annotations electronically. Another use for the Remarks section is to record and annotate short-duration changes of duty status (those lasting less than 15 minutes), such as stopping for a few minutes to check the cargo securement. If you're temporarily exempt from some hours of service regulations because of an emergency or adverse condition, you should note that in the Remarks section, too. Finally, in the Remarks section, you should also identify the loads you picked up. One way (but not the only way) to identify a load is to enter the bill of lading number in the Remarks section.

Not quite. The answer is off-tracking.

When any vehicle turns, its rear wheels will follow a shorter path than its front wheels. This is called off-tracking or "cheating." The longer the vehicle, the greater the difference. In a combination vehicle, the trailer's wheels will off-track more than the tractor's rear wheels. In a double or triple combination vehicle, the wheels of the last trailer will off-track the most.

Not quite. The answer is Both of the above

Multi-speed rear axles (which tend to be less common in today's CMVs) and auxiliary transmissions provide additional gears that you can select while you drive. You select the additional gears with a control switch on the gearshift lever.

Not quite. The answer is U-joint

A universal joint (U-joint) connects two shafts to enable them to rotate together, even if they are at an angle to each other. As part of the drivetrain, one U-joint connects the transmission shaft to the drive shaft, and another U-joint connects the drive shaft to the input shaft of the differential. These U-joints are critical. If the drive shaft comes loose at one end, it may dig into the pavement, causing loss of vehicle control.

Not quite. The answer is a yellow malfunction lamp on the left side of the dolly.

If the converter dolly has ABS, there will be an ABS malfunction light on the left side.