Detailed Inspection Procedures
Follow these structured procedures to ensure a thorough pre-trip inspection of your commercial vehicle. These procedures are designed to meet FMCSA requirements and industry best practices.
Air Brake Check Procedure
- Start engine and build air pressure to governed cut-out (120-140 psi)
- Turn off engine, release parking brake, press and hold brake pedal
- After initial pressure drop, monitor for continued loss (should not exceed 3 psi in 1 minute for straight trucks or 4 psi for combinations)
- Start engine and rebuild pressure, check governor cut-in (around 100 psi)
- Fan brakes to reduce tank pressure. Low air warning should activate before 60 psi
- Continue fanning brakes. Spring brakes should activate at 20-40 psi
- Rebuild pressure, check for proper brake adjustment by moving forward slowly and applying brakes
Coupling Inspection Procedure
- Check that fifth wheel is securely mounted to frame
- Ensure fifth wheel jaws are closed around kingpin
- Verify release lever is properly seated and safety latch engaged
- Check for adequate space between trailer and tractor frame
- Connect and verify proper attachment of air lines and electrical cord
- Fully raise landing gear and secure handle
- Perform tug test to ensure coupling is secure
Tire Inspection Procedure
- Check tire pressure with a gauge (not just by kicking)
- Inspect tread depth (minimum 4/32" on steer tires, 2/32" on others)
- Look for cuts, bulges, or sidewall damage
- Check for signs of uneven wear that may indicate alignment or inflation issues
- Ensure valve stems and caps are intact with no leaks
- Check for adequate spacing between dual tires and no debris lodged between them
- Verify all lug nuts are present and secure (look for rust trails or shiny threads)
Light Check Procedure
- Turn on all lights and walk around the vehicle
- Check headlights in both low and high beam settings
- Verify turn signals (left and right) are working on both tractor and trailer
- Check brake lights by pressing brake pedal (use a helper or mirror)
- Test 4-way flashers and ensure all marker lights are functioning
- Inspect clearance lights and reflectors for damage or dirt
- Check license plate light is operational
Top 5 FAQs
- Is a pre-trip DVIR mandatory? Yes. FMCSA requires all CDL drivers to perform a documented pre-trip inspection daily.
- What does DVIR stand for? Driver Vehicle Inspection Report.
- How long does a full DVIR take? 15–45 minutes depending on vehicle type and thoroughness.
- What happens if a DVIR is skipped? It results in DOT violations, CSA score penalties, and increased liability.
- Can I use FleetRabbit to complete it? Yes. Use the FleetRabbit app for digital DVIR logs, defect tracking, and compliance records.