Illinois CDL: Pre-Trip Inspection Practice Test

Not quite. The answer is the parking brake

The parking brake is meant to keep your vehicle from moving. The best way to test it is to apply the brake and then try to pull forward gently. The parking brake should hold your vehicle in place.

Not quite. The answer is Brake chamber

The brake chamber (one at each wheel) converts air pressure to mechanical force to operate the brake at that wheel. When you press the brake pedal, compressed air from a service tank enters the brake chamber. Air pressure pushes out the brake chamber's pushrod, which moves the slack adjuster. The moving slack adjuster applies the brake.

Not quite. The answer is 10

If there is more than 10 degrees of play in your steering wheel, your vehicle will be harder to steer. Have the problem corrected before you drive the vehicle. Ten degrees is equivalent to about 1¾ inches at the rim of a 20-inch steering wheel. According to federal regulations, there must not be more than 2½ inches of play at the rim of a 20-inch steering wheel.

Source: 49 CFR 570.60

Not quite. The answer is Check the sight glass.

Your vehicle may provide a way for you to check the coolant level even when the engine is hot. Such devices include reservoir sight glasses, see-through coolant overflow containers, and coolant recovery containers.

Not quite. The answer is Frame

The frame consists of the structural members for supporting the body of the vehicle or trailer. When inspecting the frame, (1) check for cracks; (2) check for broken welds; and (3) check for illegal holes or other damage to the longitudinal frame members, cross members, box, or floor.

Not quite. The answer is Splash guards

Splash guards (mud flaps) behind the tires prevent debris from hitting other vehicles. During your pre-trip inspection, check that splash guards are present, undamaged, securely mounted, and not dragging on the ground or rubbing on the tires.

Not quite. The answer is Spring mounts

Spring mounts consist of the brackets, bolts, shackles, and bushings used for attaching springs or air bags (for an air ride suspension) to the vehicle frame. During your inspection, check that the spring mounts are secured to the vehicle's frame and axles. Check that no bushings are damaged or missing. Check that there are no broken, loose, or missing bolts or U-bolts.

Not quite. The answer is 1/8 full.

According to the CDL manual, the DEF tank should be more than 1/8 full. (Typically, a vehicle uses about 1 gallon of DEF for every 50 gallons of diesel fuel.) Also check the DEF indicator on the dashboard to be sure it is working properly.

Not quite. The answer is Poisonous fumes can enter the cab or sleeping compartment.

The exhaust system is designed to help remove toxic gases produced by the engine. A leak in the exhaust system can allow poisonous carbon monoxide (CO) to seep into the cab or sleeping compartment. A buildup of CO is more likely in cold weather, when you may have the cab windows closed.

Not quite. The answer is Stop arm

The stop arm is an extensible stop sign on the side of the school bus. A control lets you swing out the stop arm to warn other drivers that you're stopping to pick up or let off passengers. During your inspection, check that the stop arm is undamaged and mounted securely on the vehicle frame, and there are no loose fittings. Activate the stop arm to be sure that it extends fully.

Not quite. The answer is Over the trailer bumper; hooks face downward

During your pre-trip inspection, make sure that the safety chains are crossed (if they are long enough for that). Make sure that the safety chains are hooked over the trailer bumper and onto the trailer so that the hooks face downward.

Not quite. The answer is Non-steering axle tires

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 Locking pins

On many vehicles, the fifth wheel is designed to slide forward and backward on slider rails. If that is so on your vehicle, check the sliding fifth wheel locking pins. Make sure that none of them are loose or missing and that all of them are fully engaged.

Not quite. The answer is do either (a) or (b).

If the coolant overflow container is not part of the pressurized system, you can remove the cap to check the coolant level even when the engine is hot. Alternatively, some vehicles have sight glasses to let you check the coolant level. Note: Never attempt to remove the radiator cap or any other part of the pressurized system until the system has cooled thoroughly. While it's hot, pressurized steam or boiling water can spray out and injure you.

Not quite. The answer is the support frame.

As part of your vehicle inspection test, if your vehicle has a semitrailer, you will have to check the landing gear. Check that it is fully raised and no parts are missing. Check that the crank handle is secure and the support frame is undamaged. If the landing gear is power operated, check for air or hydraulic leaks.

Not quite. The answer is do all of the above.

As part of your vehicle inspection test, if your vehicle is equipped with a cargo lift, explain how to check it for correct operation. Check for leaking, damaged, or missing parts. Also check that the cargo lift is fully retracted and securely latched.

Not quite. The answer is Release arm

The release arm allows you to disengage the fifth-wheel locking jaws so you can uncouple the trailer. During your pre-trip inspection, check that the release arm is in the engaged position and the safety latch (if so equipped) is in place.

Not quite. The answer is Brake hoses / lines

Compressed air (or hydraulic fluid if your vehicle has hydraulic brakes) flows to the brakes through hoses and lines. During your pre-trip inspection, check all hoses and lines for leaks or tangles.

Not quite. The answer is slack adjusters.

The slack adjuster connects to the pushrod. If the slack adjuster has too much slack, the brake can fail.

Not quite. The answer is Shock absorbers

During your pre-trip inspection, check the shock absorbers on every axle of your vehicle (including the trailers if any) to be sure that they are securely mounted and not leaking.