Tractor-trailers can weigh up to 80,000 lb. if you count the semi, trailer and cargo. Operating a heavy tractor-trailer can be dangerous, so drivers undergo extensive training to earn their CDLs and start their careers.
Whether studying for your CDL test or heading to your next customer, pre-trip inspections help you catch problems with your vehicle or trailer. Unchecked issues can lead to accidents or extensive repairs.
Do you know how to perform a pre-trip inspection? Need a quick refresher? Follow our guide to pre-trip inspections to learn the basics. Reach out to our Safety Department for more in-depth information.
Use these quick links to jump to sections of the article:
- The Engine Inspection
- Driver Door Area & Tires
- Trailer Pre-Trip Inspection
- Lights & Reflectors
- In-Cab Pre-Trip Inspection
Large Truck Crash Statistics
Knowing how to operate a semi-truck safely in various conditions is imperative for drivers. In 2019, there were 510,000 large truck crashes, according to FMCSA’s 2021 Pocket Guide to Large Truck and Bus Statistics.
Of these crashes, 4,479 were fatal, and 114,000 were injury crashes involving large trucks. Most fatal large truck crashes involved those weighing more than 33,000 lb.
Accidents happen. Drivers can mitigate their risk of an accident by being responsible behind the wheel, following federal regulations and performing pre- and post-trip inspections.
Your Pre-Trip Inspection Checklist
Drivers must provide a vehicle inspection report at the end of each day. Vehicle inspection reports list any issues that could affect the vehicle’s operation and safety. Inspecting vehicles before and after each trip helps catch problems and keep drivers safe.
At a minimum, each report covers the following parts of a vehicle:
- Coupling devices
- Emergency equipment
- Horn
- Lights and reflectors
- Mirrors
- Parking brakes
- Service brakes
- Steering mechanism
- Tires and rims
- Windshield wipers
Pre-trip inspections take around 15 to 20 minutes. You’ll examine your truck and trailer to ensure it’s ready for the trip.
Before every haul, you should check that you have your license, registration, medical card, updated inspection sticker and FMCSA Safety Regulation manual. If you’re picking up a trailer, always make sure the trailer number matches the number listed on your assignment.
Follow these steps to inspect your tractor-trailer, and watch our video on Prime’s pre-trip inspections. Chock your tires before you begin, so the vehicle doesn’t roll or slip.
Under the Hood: Examining the Engine
Start your pre-trip inspection by looking at the engine. Lower the gear guard so you can open the hood. Remove pins and unlatch the hood to do so. Once the hood is open, step back and look underneath the truck to see if there are any leaks.
Passenger Side
On the passenger side, make sure that your general hoses and alternator are free of cuts, abrasions or cracks. Hoses should be sufficiently secured, exhibiting no signs of leaks.
Driver’s Side
Walk around to the driver’s side and conduct a similar examination. Look at the parts listed below for signs of wear, abrasions and leaks. Your coolant and oil levels should be filled to the manufacturer’s specifications. Keep an eye out for fraying belts, improperly secured parts, and missing castle nuts and bolts.
- Air compressor
- Belt-driven water pump
- Coolant reservoir
- Gearbox and hoses
- General hoses
- Oil
- Power steering fluid
- Power steering pump
- Shock absorber
- Spring hangers and arm
- Steering linkage
Check Your Brake System
Drivers must check the brake hose, brake chamber and slack adjuster. When pulled by hand, the push rod should not move more than 1” with the brakes released.
Your brake line should be free of debris and oil, and the hose material shouldn’t be worn too thin.
Outside Driver Door Area & Tires
If the engine looks good, inspect the outside of the truck.
- Check your mirror on the driver’s side to ensure it is clean and firmly mounted to the vehicle.
- Open the driver’s door, and examine the door’s seals and hinges for cracks or dry rot.
- The fuel cap should be on tight, and the fuel seal should not leak.
- Ensure that the catwalk and steps at the back are clear of any objects or debris.
In addition to the steps above, drivers should look at the following parts for damage, wear or debris buildup:
- Air bag
- Brake hose, chamber, lining and drum
- Drive shaft
- Exhaust
- Frame and cross members
- Shock absorber
- Spring hangers and arm
- U-joints and bolts
Check Your Tires (All of Them!)
The tires on your tractor-trailer should have a tread depth of no less than 0.125” and be aired according to the manufacturer’s standards. You can check the air pressure with a gauge and adjust it based on your load and the temperature.
The rims shouldn’t be bent or broken, and there shouldn’t be cracks around the bolt holes. Behind the tire, the mud flap should not be tattered or loosely attached to the vehicle. There should be space between the mud flap and the tire.
Trailer Pre-Trip Inspection
Is the truck good to go? Check! Now it’s time to inspect the trailer. Walk around the trailer and examine it for cracks, abrasions or broken parts.
- Air bags
- Brake hose, lining and chamber
- Bulkhead
- Frame and cross members
- Shock absorbers
You’ll also want to check that:
- The landing gear is fully-raised with the crank handle secure in its cradle. The landing gear and mud flap should be a proper distance apart.
- The tandem relief’s handle and locking pins are in the fully-locked position.
- The slack adjuster and push rod don’t move more than 1” when pulled by hand.
The back doors of the trailer should latch properly. The trailer’s lock rods and hinges must be intact and not bent. Your trailer should also have door chains for safety when loading and unloading.
Coupling: Back of Tractor, Front of Trailer
A driver’s next step is to examine where the tractor and trailer connect.
- Electric line — Ensure there are no exposed wires. The line should be secure.
- Air line — Your air line should be secured at both ends and not leaking.
- Gladhands — Check for worn or rotted seals on gladhand couplings. Make sure there are no leaks in the gladhands connected to the trailer’s air brakes.
- Trailer apron — No gap should exist between the apron and the skid plate. The skid plate should be lubed.
You should also check the kingpins, mounting bolts, and the sliding fifth wheel and locking pin.
Refrigerated Trailer Inspections
When you inspect one of Prime’s refrigerated trailers, you start by selecting the “pre-trip” option on the trailer’s display. It will take the reefer 10 to 15 minutes to complete a self-inspection and notify you of anything in need of adjustment or repair.
While the reefer’s self-test runs, you should look for any signs of damage on the bottom rail, top rail and sides of the trailer. Reefers are insulated. Drivers need to examine the trailer for cracks and exposed insulation.
Lights & Reflectors
You don’t want to drive off without working lights. The lights on your truck and trailer should be securely in place, not cracked and amber in color.
- Clearance lights
- Marker lights
- Headlights
- Tail lights
- Reflective tape on trailer and mud flaps
Once you’ve checked that the lights and reflectors are intact, you should test your lights and turn signals. Climb into your cab and turn the following lights and signals on:
- Left turn signal
- Right turn signal
- Four-way flashers
- High beams
- Brake lights
In-Cab Pre-Trip Inspection
Inside your cab, you’ll check that your seat belt latches and is not too worn. Next, check that you have a fire extinguisher that’s charged. Ensure your cab has three reflective triangles under the bunk area and electrical fuses in the glove box.
Once you’ve reviewed your safety gear, adjust your mirrors, start the engine and check the dashboard’s instrument panel:
- Oil pressure — It should be rising as the engine runs.
- Voltmeter — It should show the alternator charging between 13 and 14 volts.
- Air pressure — It should be around 120 to 125 psi.
While you’re here, test the heat and air conditioning, city horn and air horn.
Air Brake Test
With your tires chocked, you can perform an air brakes test. To do so, release both brakes and turn the truck off. When you turn the truck back on, you will apply pressure.
- Apply hard pressure to the brake.
- Watch for the gauges to stabilize.
- Hold a hard brake for one minute. You don’t want to lose more than four psi during this minute.
- Pump down on the brakes until the gauges read at or before 60 psi. Your warning light and buzzer should come on.
- Pump down on the brakes until the tractor and trailer valves pop up between 40 to 20 psi.
Parking Brake Test
After testing your air brakes, you can test your parking brake. Allow the truck to rebuild its air pressure before testing the parking brakes.
- Remove wheel chock.
- Release the tractor brakes and apply the trailer brakes.
- Put the truck in “drive.”
- Give your trailer brakes a light tug, ensuring they hold.
- Switch. Release the trailer brakes and apply the tractor brakes.
- Give your tractor brakes a light tug, ensuring they hold.
- Release both brakes.
- Pull forward to 5 mph, then use the brake pedal. The truck shouldn’t pull left or right. It should come to a smooth stop.
What to Do if There’s an Issue During Pre-Trip Inspection
Contact your fleet manager or road assistance immediately if you find an issue with your tractor or trailer. Prime will take corrective action and advise you on what to do next. Repairs must be made before the tractor-trailer can be dispatched again.
Inspection violations affect both the driver’s and carrier’s records. Violations can decrease a carrier’s CSA score. FMCSA keeps records of driver and vehicle violations. These records are updated monthly.
CDL Pre-Trip Inspection Test
Truck drivers must begin each work day with a pre-trip inspection. The Class A CDL test requires new drivers to know how to do a pre-trip inspection. Student drivers must be able to identify truck and trailer parts and understand how they operate.
You’ll walk an examiner through a pre-trip inspection for that portion of the CDL test. The best way to remember what’s on a pre-trip inspection checklist is to perform inspections the same way each time. The more you practice, the more it will become second nature.
Are you ready to become a driver?
Do you need CDL training? Our Driver Training Program prepares you for your CDL exam and offers experience hauling real loads.
Apply online to start our CDL training program, or contact our Recruiting Department at 866-290-1568 for details.
