KS CDL General Knowledge cheat sheet

Kansas CDL Class A covers any combination of vehicles with a GCWR of 26,001 lbs or more, provided the towed unit exceeds 10,000 lbs; Class B covers a single vehicle of 26,001 lbs or more, or such a vehicle towing 10,000 lbs or less.

Class C covers vehicles designed to carry 16 or more passengers (including the driver) or placarded hazardous materials, when not Class A or B; a Kansas CDL also requires proof of lawful presence and Kansas residency.

Stopping distance = perception distance + reaction distance + brake lag distance + braking distance; total stopping distance at 55 mph for a loaded tractor-trailer is roughly the length of a football field.

Speed limits: 55 mph on most two-lane rural highways unless posted otherwise, 65-75 mph on many divided highways and the Kansas Turnpike; always obey the posted sign over general rules.

The Kansas point system suspends a CDL at 8 points in 12 months, 9 in 24 months, or 11 in 36 months for convictions; serious traffic violations in a CMV carry heavier penalties.

Alcohol: 0.04% BAC is the CMV limit for a commercial driver; a first offense disqualifies for one year, and a CDL holder may not use a handheld phone while driving.

Railroad crossings: a CMV carrying passengers or placarded hazmat must stop at all crossings unless the crossing is exempt; other CMVs must stop if the vehicle cannot clear the tracks or a train is approaching.

Pre-trip inspection is the driver's legal responsibility; check tires, brakes, lights, coupling devices, and load securement before each trip, and log any defect that affects safe operation.

Air brake system components: compressor, governor, air tanks (wet, primary, secondary), safety valve, drain valves, foot valve, slack adjusters, brake chambers, and the low-air warning device.

The governor cuts the compressor in at about 85 psi and out at about 100-125 psi; the low-air warning must activate before pressure drops below 60 psi, and the spring brakes apply at about 20-45 psi.

A static leak test: with engine off and tanks full, release the parking brake, hold the foot valve; loss should not exceed 3 psi per minute for a single vehicle or 4 psi per minute for a combination.

A tractor-trailer must build air pressure from 85 to 100 psi within 45 seconds at fast idle; a single vehicle must build from 50 to 90 psi within 3 minutes.

The safety valve releases at about 150 psi; if it fails, the compressor can overpressurize the system and the valve must be replaced before driving.

Slack adjusters: with the brakes released, pull the slack adjuster by hand; it should not move more than about one inch at the push rod, and it should not be adjusted by hand if it is an automatic slack adjuster.

On a long downhill grade, select a low gear before the descent and use engine braking; do not fan or pump the brakes, and do not ride the brakes continuously.

Fifth-wheel coupling: after backing under the trailer, the kingpin locks the fifth wheel; pull the tractor forward twice in a low gear to test the lock, then connect the air lines and electrical cord and check the trailer brakes.

The tractor protection valve closes and prevents air loss if the trailer breaks away; the trailer emergency (supply) line and service line must be connected correctly and the trailer brakes must release when the tractor parking brake is released.

Before driving, check the landing gear is fully raised, the mud flaps are clear, and the trailer is at the correct height; the trailer should sit level when coupled.

Off-tracking: the rear wheels of a tractor-trailer follow a shorter path than the front wheels; on a right turn, swing wide to keep the trailer wheels from running over the curb or a vehicle.

When backing a tractor-trailer, turn the steering wheel toward the direction you want the trailer to go; if the trailer drifts, pull forward and correct rather than oversteering.

A combination vehicle's stopping distance is longer than a single vehicle's, and the trailer can push the tractor (trailer jackknife) if the tractor brakes lock first; brake smoothly and keep the trailer brakes working.

The rearward amplification (crack-the-whip) effect is greatest on the last trailer in a multi-trailer combination; slow down before curves and avoid sudden steering.

The Hazmat (H) endorsement requires a TSA Security Threat Assessment, a knowledge test, and a driving record check; it is required for any vehicle carrying placarded quantities of hazardous materials.

Placards are required when the quantity of a hazardous material in a vehicle meets the placarding threshold; placards must be on all four sides of the vehicle and match the material being carried.

Shipping papers must be within reach of the driver while driving, and must include the proper shipping name, hazard class, UN/NA number, packing group, and quantity for each hazardous material.

A hazardous materials load must be secured against movement, and the driver must know the emergency response information (ERG guide number) for each material carried.

Parking rules: do not park a placarded vehicle within 5 feet of a roadway or within 300 feet of an open flame; on a highway, park only in a designated area or as far from the roadway as practical.

Smoking is prohibited within 25 feet of a placarded vehicle, and the engine must be shut off during loading or unloading of hazardous materials.

A CDL is disqualified for one year for a first conviction of driving a CMV while under the influence, and for three years if the offense occurs while carrying hazardous materials.