New Jersey CDL DMV Knowledge Test Class B 2

An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level of 125 psi. This air pressure level is referred to as the "cut-out" level.

A driver should inspect wheels before a drive, specifically looking for damage on the wheels and rims. Wheels or rims that have had welding repairs are not safe for use.

You must be at least 18 years old to obtain a CDL. However, you must be 21 years old to drive in interstate commerce or to obtain a passenger or hazardous materials endorsement.

The weight of cargo in a vehicle needs to be balanced appropriately so that it does not interfere with the vehicle's safe handling. For example, if cargo is placed too far to the rear of a vehicle, the front axle will be under-weighted and the front wheels may not have enough traction for the driver to steer safely.

The method of controlled braking involves applying the brakes as hard as you can without locking the wheels. If you need to make large steering adjustments while using controlled braking, you should remove your foot from the brake pedal, steer, then reapply the brakes.

Possible causes of vehicle fires include spilled fuel or improper use of flares following an crash; under-inflated tires or dual tires that touch; short circuits in the electrical system; smoking around fuel; improper fueling or loose fuel connections; and carrying cargo that is flammable, improperly sealed or loaded, or poorly ventilated.

The right lanes of a roadway are generally intended for vehicles traveling more slowly than surrounding traffic. If being slowed down by a heavy load, you should stay in the right lane.

Missing clamps, spacers, studs, or lugs can be a dangerous defect. Mismatched, bent, or cracked lock rings are not safe to be used. Wheels or rims with welded repairs are not safe.

Black ice is a thin layer of ice that is clear enough for the road surface to be seen through it. A road covered in black ice may look like it is merely wet.

A convex mirror makes objects seem smaller and farther away than they actually are.

When stopping, the brake pedal should be pushed down gradually. Control the pressure so your vehicle comes to a slow, safe stop.

Being under stress can lead to aggressive driving, which is dangerous. Playing calming music can help you become more relaxed if you are feeling stressed while driving.

If you are asked to alley dock, you should first pull past the alley and stop your vehicle in a position that is parallel to the outer boundary. From there, you should back your vehicle entirely into the alley parking area. Your vehicle should be parked in a straight position within the boundaries of the parking space.

To reduce the chances of becoming fatigued on a long trip, a driver should stop for a break at least once every two hours or 100 miles driven.

Bus mechanics are required to have passenger endorsements.

To prevent drowsiness on a long trip, strategies include getting adequate sleep beforehand; planning out the route and stopping points in advance; driving with a passenger; and driving at times during which you are normally awake.

On a downgrade, the braking effect of the engine should be your primary method of controlling speed. Shift down to a lower gear before starting down the hill and save the brakes for additional slowing or stopping that may be required by road or traffic conditions.

While driving, you should continually scan the road to spot potential hazards in advance. Make emergency plans for how to deal with the hazards if they become dangerous.

If you encounter an aggressive driver, the most important thing to do is get out of their way, if possible. Do not provoke the driver by challenging them or making eye contact, and do not let yourself be provoked by rude gestures they might make.

If you must drive in fog, you should use your low beam headlights and fog lights, even during the day.

Backing a large CMV is always dangerous because you will not be able to see everything behind you. If you must back up, use a helper, if possible.

Prescription and over-the-counter medications may have side effects that can impair a person's ability to drive safely. It is illegal to operate a motor vehicle while under the influence of alcohol or any other controlled substance, including some over-the-counter medications.

Backing maneuvers that may be included in the basic vehicle control skills test include straight line backing, offset back/right, offset back/left, driver side parallel parking, conventional parallel parking, and alley docking.

Accelerate smoothly and gradually. Rough acceleration can cause mechanical damage.

If you stay in neutral for too long while double clutching and have difficulty switching your vehicle into the next gear, don't force it. Return to neutral, release the clutch, increase the engine speed to match road speed, and try again.

After starting a vehicle's engine, the oil pressure should come up to a normal level within seconds. Do not operate a vehicle if it has oil pressure that is low, dropping, or fluctuating.

Stopping is not always the safest option when responding to an emergency while driving. It is usually safer to steer out of the way when attempting to avoid a crash.

If you drive over a bridge during the on-road driving skills test, the examiner may ask you afterwards to recall the bridge's posted weight limit.

Failure of hydraulic brakes is often caused by a loss of hydraulic pressure. Hydraulic brakes may also fade because of overuse on a long downgrade.

Defects to check for when inspecting your vehicle's suspension system include cracked or broken spring hangers; missing or broken leaves in a leaf spring; and leaking shock absorbers. If you spot any of these issues, be sure to have them repaired.

Before driving, you should always verify that your service brakes are in good working order. Testing the brakes before a trip allows you to locate any problems before you need to brake while on the road.

Driving while fatigued can be extremely dangerous. Strategies for preventing drowsiness while driving include getting a full night's sleep before a trip; having someone ride with you so you can take turns driving; scheduling trips for times during which you are normally awake; and avoiding medications that may cause drowsiness.

Brakes heat up with use. If they are overused and become too hot, expansion and chemical changes will make them less effective and eventually cause them to stop working altogether. This is known as "brake fade."

In an air brake system, the air compressor is connected to the engine through gears or a v-belt.

If at least one-fourth of the leaves in a leaf spring are missing, the vehicle will be put out-of-service until the defect is fixed.