Modernized Class A CDL Pre-Trip Inspection: The Full Test-Day Order

The pre-trip inspection is the first skills test you take, and it’s where a lot of CDL applicants lose points. They usually know the truck. What goes wrong is not saying out loud what they’re checking. The modernized pre-trip format many states now use has made the test shorter and more structured, so it’s easier to learn if you follow the order.

This post walks through the modernized Class A pre-trip in test order, the way a CDL school teaches it. For a side-by-side of what changed from the old format, see our breakdown of the new modernized CDL pre-trip and how it’s graded.

The two phrases that carry your whole pre-trip

Nearly every item on the inspection comes down to one of two phrases. Memorize both.

Tip: Examiners score what they hear, not what you look at. If you check a part without saying anything, it counts as not checked. Name the part and say your phrase every time.

Step 1: Exterior lights (examiner outside)

In the modernized format the examiner checks the lights first so they know the vehicle is safe before anything else happens. Turn the key to accessory and run through the lights while the examiner signals from outside:

1. Headlights (low beam), then high beams
2. Left turn signal, then right turn signal
3. Four-way flashers
4. At the rear: tail lights, brake lights, four-ways, left and right signals

Once the examiner gives the final thumbs-up, they climb into the cab with you.

Step 2: Seat belt and safe start

Before the engine starts:

• Seat belt: no cuts, frays or abrasions. It latches and unlatches properly. Put it on.
• Tell the examiner you got in using three points of contact. This is a scored item, so say it out loud.
• ABS light: key to on, and the ABS lamp should come on and then go off. If it stays on, there’s a fault.
• Safe start: foot on the brake, parking brakes set, transmission in neutral, then start the engine.

Step 3: The in-cab air brake test

This is where most of the points and most of the failures happen. The school in our source video teaches it as G-A-L-E. For a deeper look at every number, read CDL Air Brakes Explained: Every PSI Number, Test Step and Trap.

How to run it:

1. Governor: Let the air build and listen for the “sneeze” of the governor cutting out. Say what PSI it cut out at. You can raise the idle a little to speed this up, but keep it under about 1,000 RPM.
2. Engine off, key on. Once the tanks are full, shut the engine down and turn the key back to on so the gauges and warning buzzer still work.
3. Charge the system: push in the parking brake valves and wait until the trailer tanks stop hissing. A system that isn’t fully charged can’t be tested.
4. Applied: press the brake pedal firmly and hold it for 60 seconds. Keep your foot completely still, because any movement bleeds air and ruins the reading.
5. Low air: fan the brake pedal until the warning comes on for both the primary and secondary gauges. Say the PSI it came on at.
6. Emergency: keep fanning until both parking valves pop out. Say the PSI. Don’t touch the knobs. Air pressure has to pop them, and pulling them yourself can get you disqualified.

Remember: Some trainers say “before 55 PSI” for the low-air warning. The federal-based CDL Manual standard is at or before 60 PSI. That’s the number to know for the written test and the skills test.

Step 4: In-cab inspection

Restart with a safe start and let the low-air buzzer clear so the examiner can hear you. Then work from the outside in:

• Mirrors: not cracked, damaged or loose. Clean, clear and adjusted.
• Windshield: clean, no cracks, no obstructions. Say “no obstructions” out loud.
• Wiper arms and blades: arms not cracked, damaged or loose. Blades have no abrasions, bumps or cuts and make good contact with the glass. Run the washer fluid.
• Dash indicators: left and right signals, four-ways, headlights, high-beam indicator
• Horns: city horn and air horn
• Heater and defroster: check defrost airflow at the windshield and heat at the floor
• Emergency equipment (3 items):
  1. Spare electrical fuses
  2. Fire extinguisher: mounted securely, charged (check the gauge), pin in the handle
  3. Three reflective warning triangles

Step 5: The tug test and service brake check

With air back at governor cut-out:

1. Trailer brake: tractor parking brake released, trailer parking brake set. Put it in gear and pull gently. It should hold, and the pull also proves the trailer is coupled.
2. Tractor parking brake: tractor brake set, trailer brake released. Pull gently. It should hold.
3. Service brake: release both, check your mirrors, roll forward at about 5 mph, and brake firmly with a loose grip on the wheel. If the truck pulls left or right, the brakes may be out of adjustment or there may be a suspension problem.

Set the brakes, put it in neutral, and tell the examiner the in-cab portion is complete.

Step 6: Exterior overview and engine compartment

Overview first: check that the truck isn’t leaning (a lean can mean a broken spring, a low tire or a shifted load) and that there are no fluid puddles underneath.

Front lights: headlight lenses are clear, turn signals are amber, cab marker lights are amber, and trailer clearance lights are the right color. None are cracked, damaged or loose.

Under the hood, in this order:

1. Three fluids: coolant (between min and full), engine oil (dipstick in the safe range; say how you’d wipe it and re-read it), power steering (between add and full). For each one, check the reservoir, cap and hoses.
2. Hose overview: air, fuel and oil lines. Look and listen for leaks, abrasions, bumps and cuts.
3. Steering: no more than 10° of free play in the steering shaft, gearbox securely mounted with no shiny threads or rust trails at the bolts, linkage secured with castle nuts and cotter pins
4. Suspension: leaf springs not missing, broken or shifted, spring hangers, U-bolts, bump stop, shock absorber (not leaking)
5. Brakes: brake line and ABS line with no abrasions, bumps or cuts. Shoes with at least ¼ inch of lining. Drum with no cracks or illegal welds, and no contaminants such as oil, grease or dirt.
6. Steer tire: sidewalls, 4/32” tread in every groove, a matched pair, a good bead seal, the rim with no illegal welds, all lug nuts present with no rust trails, a valve stem with its cap on, and pressure to the manufacturer’s spec checked with a gauge

Did you know? You have to say you’d check tire pressure with a tire gauge. Thumping the tire isn’t an acceptable method on the test.

Step 7: Side of tractor, coupling and trailer

• Mirror: clean, no illegal stickers, securely mounted
• Battery box: you usually don’t have to open it. Explain how you’d check the mounting, cracks or leaks, cable condition and corrosion.
• DEF: cap intact. The tank is secured by its straps.
• Fuel tank: cap and seal, safety chain, fuel lines, tank straps. No leaks.
• Electrical line: plug seated, safety catch in place, no missing or corroded pins
• Air lines: red is emergency, blue is service. Neither leaks. Glad hands have good rubber seals and no debris inside. Lines are supported and not dragging on the catwalk, and the catwalk is clear.
• Frame: not cracked, damaged or loose, and no illegal welds
• Fifth wheel: no gap between the fifth wheel and the trailer apron (a gap means a high hitch), properly greased, mounting bolts tight, release handle in the locked position, locking jaws closed around the kingpin. On a sliding fifth wheel, add the slide locks, clean rails and the slider air line.
• Kingpin and apron: not bent, cracked or damaged
• Landing gear: enough clearance from the tractor for turns, cross members intact, pads clear, crank handle stowed, gear fully raised
• Trailer: DOT reflective tape covering at least 50% of the trailer’s length (FMCSA conspicuity rules), frame and floor, trailer ABS lamp, and the rear lights and markers are the right color

For the full walk-around with every component listed, bookmark our complete Class A pre-trip guide.

Common point-losers on the modernized pre-trip

Lock in the knowledge before test day

The skills test is hands-on, but every number in it comes from the CDL Manual, including 60 PSI, 20–45 PSI, 4/32”, and 10° of steering play. Those same numbers show up on your written General Knowledge and Air Brakes tests. If you drill them as multiple-choice questions, you’ll recall them automatically while the examiner is sitting next to you.

The CDL Test app gives you complete practice for the CDL General Knowledge test and all endorsements, with an explanation on every question that ties the answer back to the Manual. It’s part of the Commercial Driver Prep suite: 1200+ questions across 3 focused apps, covering CDL, HazMat and Air Brakes.

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