MI CDL General Knowledge flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Total stopping distance

The sum of perception distance, reaction distance, brake lag distance, and braking distance. At 55 mph a loaded rig needs roughly a football field on dry pavement.

Brake lag distance

The distance traveled while air pressure travels through lines before brakes engage. At 55 mph this adds about 32 feet for air brakes, unlike hydraulic brakes.

Following distance rule

Allow one second for each 10 feet of vehicle length at speeds under 40 mph, plus one extra second. Above 40 mph, add one more second.

Hydroplaning speed

Hydroplaning can begin at speeds as low as 30 mph with low tire tread or standing water. Release the accelerator and avoid hard braking.

Night high-beam rule

Dim high beams within 500 feet of an oncoming vehicle and within 200 feet when following another vehicle to avoid blinding other drivers.

Railroad crossing rule

Never shift gears while crossing tracks. If your vehicle stalls on the tracks, get everyone out and away before calling for help.

Tiedown strength rule

The combined weight of tiedown assemblies must equal at least 50% of the cargo weight, and each assembly must hold 1.5 times its working load limit.

Cargo recheck interval

Inspect cargo and tiedowns before driving, recheck within the first 50 miles, then every 150 miles or 3 hours thereafter.

Oversized load flags

Red flags are required on overhanging loads. Cargo must not obscure lights, reflectors, mirrors, or the license plate.

Front-end structure rule

The front structure of the cargo space must contain the cargo if it shifts forward; the rear structure must withstand 50% of cargo weight.

Normal air pressure

Normal operating pressure is 100-125 psi. The low-air warning buzzer or light must activate before pressure drops below 60 psi.

Governor cut-in/cut-out

The governor cuts the compressor in at about 85 psi and out at about 125 psi. Pressure should build from 85 to 100 psi within 45 seconds.

Spring brake application

Spring brakes apply automatically when air pressure drops to 20-45 psi. The parking brake knob pops out when pressure is too low.

Static leak test

With engine off and brakes released, pressure should not drop more than 3 psi in one minute. With brakes applied, no more than 4 psi per minute.

Safety valve release

The safety valve releases at about 150 psi. If it releases below 150 psi, the system needs repair before driving.

Pre-trip inspection timing

A pre-trip inspection must be done within the last 24 hours and covers engine compartment, cab, lights, walk-around, and brake checks.

Tire tread minimums

Front tires need at least 4/32 inch tread depth; all other tires need at least 2/32 inch. Check inflation and damage during the walk-around.

En route inspection

Check cargo and tiedowns within the first 50 miles, then every 150 miles or 3 hours. Report any safety defects found.

Post-trip inspection

Completed at the end of each workday and reported. Defects affecting safety must be noted and repaired before the vehicle is driven again.

Curve control

Slow down before entering a curve, maintain a steady speed through it, and accelerate gently after. Sudden movements can cause a skid.

Backing safely

Use a helper and check the area first. If no helper, back slowly and check mirrors frequently. Never back when uncertain of clearance.

Hill parking

Set the parking brake, chock the wheels, and turn wheels toward the curb or away from traffic depending on the slope direction.

Double-clutching

Required in some non-synchronized transmissions: press clutch, shift to neutral, release clutch, press clutch again, shift to gear.

Hazard scanning

Look ahead 12-15 seconds to identify hazards, scan mirrors every 5-8 seconds, and check blind spots before changing lanes.

Downgrade gear use

Use a lower gear and engine braking on downgrades. Do not ride the brakes, which can cause brake fade and loss of control.

Turn signal distance

Signal at least 100 feet before turning. Signal early to give other drivers time to react to your intentions.

Four-way flashers

Use four-way flashers when driving slowly below 40 mph or when stopped in a hazardous position to warn other drivers.

Space cushion rule

Keep at least one car length for each 10 mph of speed in front, and avoid driving in others' blind spots to maintain escape room.

Property HOS limits

Property-carrying drivers: 11-hour driving limit after 10 consecutive hours off duty, 14-hour on-duty window, and 60/70-hour limit in 7/8 days.

30-minute break rule

A 30-minute break is required after 8 cumulative hours of driving without at least a 30-minute interruption of driving.

CDL alcohol limit

CDL holders are subject to a 0.04% BAC limit. A violation results in disqualification and possible license suspension.

Test refusal penalty

Refusing a BAC test results in automatic disqualification for at least one year for a first offense and longer for repeat offenses.