A driver is not expected to diagnose every mechanical failure, but must identify unsafe conditions, report defects, and avoid operating equipment that is likely to cause a breakdown or violate safety rules. A repeatable inspection and roadside plan protects both safety and paid miles.
High-value pre-trip checks
- Tires and wheels: pressure, tread, cuts, bulges, exposed cord, uneven wear, loose or missing hardware, and hub leaks.
- Brakes and air: hoses, chambers, drums or rotors, linings, warning devices, pressure build, and leakage tests.
- Fluids and cooling: oil, coolant, power steering fluid, visible leaks, belts, hoses, and abnormal temperature.
- Coupling: fifth-wheel engagement, kingpin and jaws, mounting, air and electric lines, and landing gear.
- Visibility and communication: lamps, reflectors, windshield, mirrors, wipers, horn, and warning equipment.
Stop or continue?
Stop in a safe place when a defect affects braking, steering, tire integrity, coupling, required lighting, air pressure, overheating, fuel leakage, or securement. Warning lamps, smoke, strong odors, rapid pressure loss, vibration, or a sudden change in handling require investigation. Do not let schedule pressure turn an unknown safety defect into a road call or crash.
Safe roadside response
- Move as far from traffic as the vehicle can safely travel; do not continue if movement itself is unsafe.
- Use hazard flashers and required warning devices according to the situation and company procedure.
- Tell dispatch the exact location, direction of travel, nearest marker or exit, load status, and whether traffic is obstructed.
- Describe symptoms, gauges, warning lights, sounds, smells, and visible damage without guessing at a repair.
- Stay in a safe location and follow emergency instructions when fire, spilled cargo, hazmat, or a traffic hazard is involved.
Information a repair provider needs
Provide the tractor and trailer make or type, unit numbers, tire position or component location, fault codes, required tire size, and whether the truck can be moved. Photos can help when it is safe and permitted to take them. Ask for an estimated arrival time and confirm who authorizes charges.
Document the defect and repair
Record when the defect was found, who was notified, the repair provider, work completed, parts replaced, and clearance to return to service. FMCSA no longer requires a no-defect DVIR for most interstate property-carrying operations, but defects that could affect safe operation still require reporting and correction under applicable rules and carrier procedures.
Drivers can search the truck repair directory by city and use the CDL pre-trip checklist to build a consistent inspection route.