Pre-Trip Inspection Checklist

The pre-trip inspection is the first part of the CDL skills test — and the most commonly failed. Examiners watch every move you make. Here's exactly what they check.

Engine Compartment

• Engine oil level — not below minimum, not above maximum
• Coolant level — visible in overflow tank or radiator
• Power steering fluid and windshield washer fluid
• Belts and hoses — no cracks, proper tension
• Leaks — no dripping fluids under the vehicle

Cab Check

• Seat belt works properly
• Mirrors — clean, properly adjusted
• Horn, windshield (no cracks), wipers
• Brake pedal — firm, no unusual play
• Parking brake — holds when applied
• Air brake pressure builds to cut-out (100-125 PSI)

Exterior Walk-Around

• Headlights, tail lights, brake lights, turn signals
• Clearance lights and identification lights
• Tires — proper inflation, adequate tread (4/32" on steer axle)
• Wheels and lug nuts — no cracks, no loose nuts
• Coupling devices — fifth wheel, kingpin, safety latch
• Emergency equipment — fire extinguisher, triangles/ flares

Air Brake Specific

• Air pressure builds from 85 to 100 PSI within 3 minutes
• Low-pressure warning activates between 55-60 PSI
• Spring brakes hold at normal cut-out pressure
• Slack adjusters — within adjustment range