Indiana CDL General Knowledge cheat sheet

Pre-trip inspection has seven steps: vehicle overview, engine compartment, cab checks, walk-around inspection, brake check, light check, and final review of paperwork and load.

The three-part air brake test is the static leak test (compressor build-up, governor cut-out near 120-125 psi, leak-down limits), the applied leakage test with the brake pedal held, and the low-pressure warning test.

Minimum air pressure before moving: compressor must build from 85 to 100 psi within 45 seconds at 1,000 rpm; governor cut-out at 120-125 psi, cut-in about 20 psi below cut-out.

Static leak limits: with engine off and brakes released, pressure loss must not exceed 3 psi in one minute (single vehicle); with the brake pedal fully applied, loss must not exceed 4 psi in one minute.

Low air warning must activate before pressure drops below 60 psi; the spring/parking brake must apply automatically between 20 and 45 psi.

Slack adjuster check: with the brake applied, the push rod should move no more than about 1 inch (25 mm) on a type 30 chamber; 90-degree angle between push rod and slack adjuster is the target.

Tire defects that fail inspection: tread depth below 4/32 inch on front tires or 2/32 inch on other tires, cuts, bulges, sidewall separation, exposed cord, or mismatched dual tires.

Walk-around covers: wheels and rims, lug nuts and rust streaks, suspension, frame, exhaust, coupling devices, lights and reflectors, load securement, and rear splash guards.

Total stopping distance = perception distance + reaction distance + brake lag distance + braking distance; at 55 mph a loaded rig needs roughly the length of a football field.

Perception distance is the distance traveled during the driver's recognition time; reaction distance begins when the driver decides to brake and ends when the brake pedal is pressed.

Brake lag distance on air brakes is about 32 feet at 55 mph because air must travel through the lines before the brakes apply.

Speed and stopping distance scale with the square of speed: doubling speed roughly quadruples braking distance.

Backing rules: back only when necessary, use a helper or get out and check, back toward the driver's side (left) when possible, and start steering from the correct position.

Turning: use the pivot point (rear axle of the tractor) to judge the path; swing wide enough to keep the rear wheels from off-tracking over curbs or into other lanes.

Retarders (engine brakes, exhaust brakes) help on long downgrades but must be switched off on slippery surfaces; they do not replace service brakes.

Steering is done with both hands; hand-over-hand is prohibited in most jurisdictions when turning, but push-pull steering keeps control.

Manual transmission: shift up at governed rpm minus a margin, and shift down before the engine lugs; do not coast with the clutch depressed or in neutral.

Double clutching is required in non-synchronized (crash box) transmissions: clutch in, shift to neutral, clutch out, match engine speed, clutch in, shift to gear.

RPM and road speed relationship: each gear has a limited speed range; downshifting must occur before speed falls below the gear's minimum.

Progressive shifting raises the shift point in lower gears and lowers it in higher gears to save fuel; skip shifting is used when light or empty.

On downgrades, select a gear before the descent that keeps the engine below the governed rpm without using the service brakes continuously.

Automatic transmissions: use the selector as intended; do not shift into neutral at stops or while moving, and use the retarder or engine brake position for descents.

Upshifting on a grade: complete the shift before the engine loses power; if the shift is missed, return to the lower gear rather than forcing the higher one.

Lugging the engine (running below the power band) causes overheating and can damage the drivetrain; downshift as soon as the engine begins to labor.

Visual search pattern: look 12-15 seconds ahead of the vehicle, and check mirrors every 5-8 seconds.

Following distance for a CMV at speeds under 40 mph is at least one second per 10 feet of vehicle length plus one second; a 60-foot rig at 40 mph needs about 7 seconds.

At speeds above 40 mph, add one additional second to the following distance calculation.

Blind spots: the area to the right of the cab and directly behind the trailer are the largest; use mirrors to cover the left, right, and front.

Communicate with turn signals at least 100 feet before a turn (more in some states), brake lights, four-way flashers, headlights, and horn.

Use the horn only to warn others; a light tap or a loud blast depending on the situation, and never as a greeting.

At night, dim high beams within 500 feet of an oncoming vehicle and within 200 feet when following another vehicle.

When a vehicle passes, do not speed up; maintain speed and flash headlights when it is safe for the passer to return to the lane.

Space cushion: keep at least one lane's width on both sides when possible, and a following distance of 7 seconds for a 60-foot rig at highway speed.

Overhead clearance: know your vehicle height, including load; most bridges are marked, and low-clearance warnings appear in advance.

Rear space: keep a following vehicle from tailgating by increasing your own following distance and slowing gradually, never by braking hard.

Lane position: on a multi-lane road, drive in the lane that keeps you away from oncoming traffic and allows an escape route.

At intersections, stop behind the stop line, crosswalk, or edge of the intersecting road; do not block the crosswalk.

Space to merge: enter a freeway at or near the speed of traffic, and use the acceleration lane fully before merging.

Hills and curves: reduce speed before the curve, and on a downgrade select a gear that holds speed without continuous braking.

Pedestrians and cyclists: give at least 3 feet of clearance when passing a cyclist where required, and stop for pedestrians in crosswalks.

Hazard perception: scan for clues such as brake lights ahead, merging traffic, construction signs, and pedestrians near the roadway.

If a hazard appears, the first action is to slow down and increase following distance; do not swerve unless stopping distance is insufficient.

Emergency braking: apply the brakes firmly and steer as needed; do not pump air brakes, and keep the heel of the foot on the floor for leverage.

Tire blowout: hold the steering wheel firmly, keep the vehicle straight, ease off the accelerator, and brake gently once control is regained.

Brake failure: downshift, use the parking/emergency brake gradually, and look for an escape ramp or a safe off-road area.

Off-road recovery: do not brake hard or jerk the wheel; slow gradually, then steer back onto the pavement when the shoulder is clear.

Stalled vehicle on railroad tracks: get everyone out and away from the tracks, then call the number on the crossing signal or 911.

Fire: stop, shut off the engine, get passengers out and away, and call emergency services; do not open the hood if the fire is under it.

Skids are caused by driving too fast for conditions, oversteering, overbraking, or accelerating too hard on a slippery surface.

To recover from a rear-wheel skid, steer in the direction you want the front of the vehicle to go, and do not apply the brakes.

To recover from a front-wheel skid, ease off the accelerator and steer straight ahead until traction returns.

On ice and snow, reduce speed and increase following distance; braking distances can be many times longer than on dry pavement.

Use the brakes gently and progressively; locked wheels lose steering control, so threshold braking is preferred on slick surfaces.

Hydroplaning occurs when tires ride on a film of water; ease off the accelerator and avoid braking until the tires regain contact.

Black ice forms first on bridges, overpasses, and shaded areas; reduce speed and avoid sudden steering or braking on these surfaces.

After a skid, check mirrors and traffic before resuming normal speed, and adjust speed for the conditions.

Air brake system: compressor, governor, air tanks, safety valve, brake chambers, slack adjusters, and the low-pressure warning system.

If the low air pressure warning activates, stop as soon as it is safe and do not drive until the system is repaired.

Coolant temperature gauge rising into the red indicates overheating; stop, let the engine cool, and check for leaks before continuing.

Oil pressure warning light means stop the engine immediately; continued operation can destroy the engine.

Electrical failure: if the alternator or battery warning light comes on, the vehicle may run only on battery power; stop and check the charging system.

Anti-lock braking system (ABS) lamp on means ABS is disabled but normal brakes still work; the vehicle can be driven but should be inspected.

Tire failure or flat: stop in a safe place, and do not drive on a flat tire; check the remaining tires for damage.

Steering malfunction: if steering feels loose or hard, stop and inspect; do not continue driving with a steering defect.

Federal weight limits: 20,000 lb per single axle, 34,000 lb per tandem axle group, and 80,000 lb gross vehicle weight on the Interstate System.

Bridge formula limits axle spacing; the formula is W = 500 x (LN/(N-1) + 12N + 36), where L is length in feet and N is the number of axles.

Cargo securement: aggregate working load limit of tiedowns must be at least 50% of the cargo weight for cargo not requiring a specific method.

Minimum tiedowns: one for articles up to 5 feet and 1,100 lb, two for articles up to 10 feet, and more as length and weight increase.

Tiedowns must be attached to the vehicle frame or to anchor points rated for the load, and must be tight with no slack.

Cargo must not obscure lights, reflectors, or the license plate, and must not extend more than 3 feet beyond the front or 4 feet beyond the rear without a flag.

Flags or reflectors are required on loads extending 4 feet or more beyond the rear, and at night a red light is required.

Load distribution: keep the center of gravity low and centered; shifting loads can cause rollover or loss of control.

Passenger-carrying CMV drivers must ensure passengers are seated and secure before moving, and must not allow standees where prohibited.

Emergency exit doors and windows must be clearly marked and operable; check them during the pre-trip inspection.

Hazardous materials: a CDL with the hazardous materials endorsement is required to transport placarded amounts; a background check and TSA threat assessment are required.

Placards are required for shipments of 1,001 pounds or more of a hazard class, and for any amount of certain high-hazard materials.

Hazmat loading: do not load incompatible materials together, and secure containers against movement.

Shipping papers must be within reach of the driver while driving, and must include the proper shipping name, hazard class, ID number, and packing group.

Emergency response information must accompany shipping papers; the ERG (Emergency Response Guidebook) is a common reference.

Smoking and open flames are prohibited near hazardous materials; stop the engine during loading and unloading.

Property-carrying drivers: 11-hour driving limit after 10 consecutive hours off duty, and a 14-hour on-duty window.

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

60/70-hour limit: 60 hours on duty in 7 consecutive days, or 70 hours in 8 consecutive days; reset with 34 consecutive hours off duty.

Sleeper berth split: two periods, one of at least 7 hours and one of at least 3 hours, may be combined to satisfy the 10-hour off-duty requirement.

Daily log: record duty status, total miles, vehicle numbers, and the date; logs must be current and accurate.

Fatigue signs include drifting, yawning, heavy eyelids, and missing exits; the correct response is to stop and rest, not to push on.

Passenger-carrying drivers: 10-hour driving limit after 8 consecutive hours off duty, and a 15-hour on-duty window.

ELD (electronic logging device) records driving time automatically; paper logs are used only during ELD malfunctions with a written note.

Stop at the scene, protect the area, and check for injuries; call 911 for medical help and report the accident to police.

Protect the scene: turn on four-way flashers, set out reflective triangles within 10 minutes, and place them at 10, 100, and 200 feet (or 100, 500, and 1,000 feet on a divided highway).

Do not move an injured person unless there is immediate danger such as fire or traffic.

Exchange information: names, addresses, phone numbers, license numbers, insurance details, and vehicle descriptions.

Report the accident to the motor carrier as required, and complete the accident report with all details while they are fresh.

If hazardous materials are involved, keep people away, notify emergency responders, and do not attempt to clean up unless trained.

Fire: shut off the engine, get everyone away, and call emergency services; do not open the hood if the fire is under it.

After the accident, do not discuss fault with others; provide facts only to police and the carrier.

Approach a crossing at a speed that allows you to stop before the tracks; never race a train.

Trains cannot stop quickly: a train traveling 55 mph can take more than a mile to stop.

Stop no closer than 15 feet and no farther than 50 feet from the nearest rail when a stop is required.

Required stops: at crossings marked with a stop sign, at a crossing where the view is obstructed, and when carrying hazardous materials (unless the crossing is exempt).

Never shift gears while crossing the tracks; select the gear before the crossing and maintain speed.

If the vehicle stalls on the tracks, get everyone out and away from the tracks, then call the number on the crossing signal or 911.

Do not drive around lowered gates or attempt to cross when lights are flashing; wait until the gates are fully raised and the lights stop.

At a multiple-track crossing, wait until you can see past the first track before proceeding, and check for a second train.

CDL holders are subject to the FMCSA's controlled substances and alcohol testing rules, including pre-employment, random, post-accident, and reasonable-suspicion testing.

A CDL is required to operate a CMV with a gross vehicle weight rating over 26,000 pounds, or a vehicle designed to carry 16 or more passengers including the driver.

The driver must have a valid medical examiner's certificate and meet the physical qualification standards.

Serious traffic violations (excessive speeding, reckless driving, improper lane changes) can lead to suspension or disqualification of the CDL.

Disqualification: a first offense for driving a CMV with a blood alcohol concentration of 0.04% or higher results in a one-year disqualification.

The driver must carry the CDL, medical certificate, and any required endorsements while driving.

Vehicle inspection reports must be completed daily and retained; defects affecting safety must be repaired before operation.

Texting while driving a CMV is prohibited, and handheld phone use is restricted under federal rules.