CDL-A Pre-Trip

Air Brakes — Sequence

ABS → Build Air → Applied Leak → Low Air Warning → Spring Brakes → Build Air → Parking Brake → Trailer Brake → Service Brake → Neutral / set both brakes / shut off

Air Brakes — ABS setup

Vehicle in neutral; parking and trailer brakes set; key ON; point to ABS light; verify ABS light cycles/functions; then start vehicle.

Air Brakes — Governor cutout

120–140 PSI.

Air Brakes — Build-air RPM

Raise RPM to 1000–1500 RPM while feeling for pedal looseness/stickiness/unusual noises; continue until governor cuts out.

Air Brakes — Applied leak limit

Combination vehicle: no more than 4 PSI in 1 minute.

Air Brakes — Applied leak setup

Put vehicle in gear; turn vehicle off; key ON; release parking and trailer brakes; hold brake pedal fully down; let gauges settle; time 1 minute.

Air Brakes — Low-air warning

Light and buzzer must come on no less than 55 PSI while fanning the brake pedal.

Air Brakes — Spring brakes

Spring brakes must engage between 20–45 PSI; fan pedal until parking and trailer brake knobs pop out.

Air Brakes — Rebuild after spring-brake test

Neutral; parking and trailer brakes set; start vehicle; raise RPM until governor cuts out.

Parking brake test

In gear; parking brake engaged; trailer brake disengaged; slightly tug by releasing clutch slowly; parking brake must hold.

Trailer brake test

In gear; trailer brake engaged; parking brake disengaged; slightly tug by releasing clutch slowly; trailer brake must hold.

Service brake test

Both parking and trailer brakes disengaged; pull forward slightly and apply service brake; vehicle should not veer left/right and steering wheel should not steer left/right.

Finish air-brake test

Put vehicle in neutral; engage both parking and trailer brakes; shut off vehicle.

Air-brake numbers — master

Governor 120–140 PSI → Leak ≤4 PSI/1 min → Low air ≥55 PSI → Spring brakes 20–45 PSI.

In-cab — Sequence

Lighting indicators → Emergency equipment → Seatbelt → Windshield & traffic monitors → Wipers & washers → Heater & defroster → Horns.

In-cab lighting indicators

Left turn → Right turn → 4-way flashers → Low beam → High beam. Point to each and state it functions properly.

Emergency compartment

Spare electrical fuses, light bulbs, and important paperwork.

Emergency triangles

3 reflective triangles; legal red; not cracked/damaged/broken; secured in box with nuts/bolts and lid secured.

Fire extinguisher

Fully charged; properly rated; safety pin in place; not cracked/damaged/leaking; secured with bracket, straps, nuts and bolts.

Seatbelt

Not cut, torn, or frayed; secure with nuts and bolts; latches and functions properly.

Windshield

Not cracked/damaged/broken; no illegal stickers; properly sealed all around.

Traffic monitoring devices — in cab

Not cracked/damaged/broken; secured with nuts/bolts; no illegal stickers; properly adjusted to driver.

Wiper arms and blades

Not cracked/damaged/broken; secured with nuts/bolts; proper tension to clear fluid and dirt.

Windshield washers

Operate correctly; proper spray pattern; correct fluid.

Heater and defroster

Both function properly; demonstrate each by placing hand over vents.

Horns

City horn functions properly; highway/air horn functions properly.

Walk-around — External light operation sequence

Front: running/clearance → low beam → high beam → turn signals → 4-ways. Rear: running → brake → turn signals → 4-ways.

Front clearance lights

Not cracked/damaged/broken; secured; amber; no excessive moisture; properly sealed; none missing.

Headlights

Not cracked/damaged/broken; secured; clear; no excessive moisture; functions: low beam and high beam.

Front turn signals

Not cracked/damaged/broken; secured; amber; no excessive moisture; functions: running lights, turn signals, 4-way flashers.

Engine-area sequence

Lights → Coolant → Power steering → Oil fill/dipstick → Washer reservoir → Fluid leaks → Air compressor → Air lines.

Coolant reservoir

Not cracked/damaged/leaking; proper level; secured with nuts/bolts.

Coolant cap

Not cracked/damaged/leaking; secured and tight.

Coolant hoses

Not cracked/damaged/leaking; secured at both ends with clamps.

Power steering reservoir

Not cracked/damaged/leaking; proper level; secured with nuts/bolts.

Power steering cap

Not cracked/damaged/leaking; secured and tight.

Power steering hoses

Not cracked/damaged/leaking; secured at both ends with clamps.

Oil fill tube

Not cracked/damaged/broken/leaking; secured with nuts/bolts.

Oil fill tube cap

Not cracked/damaged/broken/leaking; secure and tight.

Oil dipstick tube

Not cracked/damaged/leaking; secured with nuts/bolts; houses dipstick; dipstick properly secured.

Oil dipstick procedure

Ask examiner whether they want oil level checked. If yes, pull dipstick and explain while demonstrating; if no, leave inserted and verbally explain process.

Washer-fluid reservoir

Not cracked/damaged/leaking; filled to proper level; cap secure and tight.

Fluid leak check

Look under vehicle: no fluid leaks on ground. Check engine/transmission: no coolant, fuel, or oil leaks.

Air compressor

Not cracked/damaged/leaking; secured with nuts/bolts; gear driven.

Engine air lines

Not cracked/damaged/cut/leaking; secured at both ends with clamps, push fittings and zip ties for proper clearance.

Steering — Sequence

Steering shaft → Gearbox → Gearbox hoses → Pitman arm → Drag link → Steering arm → Tie rod → Axle.

Steering shaft

Not cracked/damaged/broken; no illegal welds; secured with nuts, bolts, universal joints; ≤10° movement; ≤2 inches on a 20-inch wheel.

Steering gearbox

Not cracked/damaged/broken; no illegal welds; secured with nuts/bolts.

Steering gearbox hoses

Not cracked/damaged/leaking; secured with clamps on both ends.

Pitman arm

Not cracked/damaged/broken; no illegal welds; secured with nuts, bolts, castle nuts and cotter pins.

Drag link

Not cracked/damaged/broken; no illegal welds; secured with castle nuts and cotter pins.

Steering arm

Not cracked/damaged/broken; no illegal welds; secured with castle nuts and cotter pins.

Tie rod

Not cracked/damaged/broken; no illegal welds; secured with castle nuts and cotter pins; nothing wrapped around it.

Axle

Not cracked/damaged/broken; no illegal welds; nothing wrapped around it.

Wheel-end — Sequence

Tire → Tread → Tire rules/inflation → Valve stem → Rim → Hub seal → Lug nuts.

Front tire condition

Not cracked/damaged/leaking; properly seated on bead.

Front tire tread

Evenly worn; no cuts, abrasions or bubbles on tread/sidewalls; 4/32 tread depth using tread-depth gauge.

Front tire rules

Same type; no radial/bias mixing; front tires cannot be recapped, retreaded, or regrooved; properly inflated.

Valve stems

Not cracked/damaged/leaking; stem caps present.

Rims

Not cracked/damaged/broken; no illegal welds; secured with lug nuts to hub; no rust trails indicating looseness.

Hub seal

Not cracked/damaged/leaking; properly secured with nuts/bolts.

Lug nuts

Not cracked/damaged/broken; properly secured; all present; no cracks/distortion; no looseness signs such as rust trails or shiny threads.

Suspension — Sequence

Vehicle level → Mounts/shackles → Leaf springs → U-bolts/spacers → Shock absorbers.

Vehicle suspension level

Suspension even; vehicle not leaning left or right; suspension functioning properly.

Mounts/shackles

Not cracked/damaged/broken; no illegal welds; secured with nuts/bolts both ends; no missing/damaged bushings; check each frame/leaf-spring attachment point.

Leaf springs

Not cracked/damaged/broken; no illegal welds; secured; none missing/shifted/cracked/broken; 1/4 or more missing/broken places vehicle out of service.

U-bolts and spacers

Not cracked/damaged/broken; no illegal welds; secured with nuts/bolts.

Shock absorbers

Not cracked/damaged/leaking; secured with nuts/bolts.

Brakes — Sequence

Brake hoses/lines → Single brake chamber → Brake pads/drums.

Brake hoses/lines

Not cracked/damaged/leaking; secured with nuts, bolts and zip ties for proper clearance.

Single brake chamber

Not cracked/damaged/leaking; properly secured with nuts/bolts.

Brake pads and drums

Free of contaminants such as debris, oil and grease.

Side-of-vehicle sequence

Lenses/reflectors → Traffic monitors → Battery box/batteries/connections → DEF → Fuel → Frames.

Side lenses/reflectors

Not cracked/damaged/broken; secured; amber; no excessive moisture; functions: running, turn signal, 4-way.

Traffic monitors — side

Convex hood mirror and door side mirrors: not cracked/damaged/broken; secured; no illegal stickers; adjusted to driver.

Battery box

Not cracked/damaged/broken; secured with nuts/bolts to vehicle frame.

Battery inspection procedure

Ask examiner whether to open battery box. If yes, inspect batteries/connections/cables; if no, leave closed and verbally demonstrate.

Batteries

Not cracked/damaged/leaking acid; properly mounted and secured with straps, brackets, nuts and bolts.

Battery connections

Not cut/damaged/frayed/spliced; no corrosion, rust or acid; all cell caps present.

DEF tank

Not cracked/damaged/leaking; secured with nuts/bolts to frame.

DEF cap

Not cracked/damaged/leaking; secure and tight.

Fuel tank

Not cracked/damaged/broken/leaking; no illegal welds; secured with straps, rubber mounts and nuts/bolts to frame.

Fuel tank cap

Not cracked/damaged/leaking; secure and tight; rubber seal inside; chain present.

Tractor/trailer frames

Not cracked/damaged/broken; no illegal welds, illegally drilled holes, or other damage to longitudinal members, cross members, or floor.

Combination — Sequence

Electrical line → Red/blue air lines → Gladhands → Fifth wheel platform → Skid plate → Release arm → Trailer apron → Locking jaws → Kingpin.

Electrical line

Not cut/damaged/frayed/spliced; connected and locked both ends; does not touch catwalk due to hangers/hanger springs.

Combination air lines

Red = emergency; blue = service. Secured/locked both ends; not cut/damaged/leaking; do not touch catwalk via hangers/hanger springs.

Gladhands

Not cracked/damaged/broken/leaking; locked; rubber O-seal not cracked/damaged/leaking; hissing indicates O-seal failure.

Fifth wheel type

Identify whether fifth wheel is fixed or slidable.

Fifth wheel platform

Secured with nuts/bolts to frame; not cracked/damaged/broken; no illegal welds.

Fifth wheel skid plate

Not cracked/damaged/broken; no illegal welds; secured to platform with locking pin; properly greased; no gap between trailer apron and skid plate.

Release arm

Not cracked/damaged/broken; no illegal welds; secured in locked position.

Trailer apron

Not cracked/damaged/broken; no illegal welds or illegally drilled holes; properly greased; no gap with skid plate.

Locking jaws

Not cracked/damaged/broken; secured with nuts/bolts; properly greased; locked around kingpin.

Kingpin

Not cracked/damaged/broken; no illegal welds or stress cracks; properly greased.

Trailer — Sequence

Landing gear → Crank handle → Support bars → Landing gear shoes → Clearance 1 → Clearance 2 → Reflective tape → Indicator lights → Rear lenses → License plate light.

Landing gear

Not cracked/damaged/broken; no illegal welds; secured with nuts/bolts; fully raised.

Crank handle

Secured with nuts/bolts; no illegal welds; stored in locked position.

Support bars

Not cracked/damaged/broken; no illegal welds; secured with nuts/bolts.

Landing gear shoes

Not cracked/damaged/broken; no illegal welds; properly greased; secured with nuts/bolts.