Newsletter
HOW TO PERFORM A PRE-TRIP INSPECTION
The careful inspection of a tractor-trailer performed by its driver is the hallmark of safety and professionalism in the commercial driving industry, and it is integral for drivers to complete an accurate and efficient inspection every time they anticipate a journey in order to become familiar with an inspection routine to a degree that it can be performed instinctually. If each time a rig is inspected it is done in an identical fashion the driver will be less likely to omit a key element of the process during a future inspection.
Front of truck
The most expedient approach to performing a pre-trip inspection is a systematic one beginning with the front of the tractor. A driver should looking for any signs of damage including the lights and reflectors on the top of the tractor, the side mirrors, the spot mirrors, the windshield, and the lights and reflectors on the bottom of the tractor. The driver should then look beneath the tractor to make sure no puddles of liquid are present that might indicate a leak in an engine component.
- lights and reflectors (top): should be clean, and not cracked or broken
- side mirrors: should be secure, clean, and not cracked or broken
- spot mirrors: should be secure, clean, and not cracked or broken
- windshield: should be clean, and not cracked or broken
- lights and reflectors (bottom): should be clean, not cracked or broken
Right side engine compartment
The driver should then, if the tractor is a conventional model, lift the engine hood and peer into the right side of the engine compartment. In the event the tractor is a cabover model the driver may wish to turn the truck's front wheels to the right to have an unobstructed view of the engine from beneath the tractor. On the right side of the engine, the driver should check the radiator, the radiator hoses, the engine fan, engine belts, the alternator, the water pump, and the oil. If the truck is a cabover, the driver should also check the coolant reservoir, as it is located on the rear rather than the left side of the engine on these trucks.
- radiator: should be secure, and not leaking
- radiator hoses: should be secure, and not leaking
- engine fan: should be secure with no broken or missing blades
- engine belts (fan, alternator and drive): should be secure and have no cracks or frays, and should have no more than ½ to ¾ of an inch of free play.
- alternator: should be secure and not damaged in any way, in particular there should be no frayed wires on the exterior of the alternator
- water pump: should be secure and not leaking
- oil: the dipstick should be pulled and the oil level observed to be between "add" and "full"
- coolant reservoir (cabover): should be secure, not leaking, and filled to the proper level
Left side of the engine compartment
After the right side of the tractor's engine is deemed safe for travel, the driver may then proceed to check the left side of the engine. If the tractor is a conventional, the driver must also check the coolant reservoir on this side, along with the air compressor, the power steering pump, the power steering hoses, the remainder of the engine hoses, the power steering fluid reservoir, the steering gearbox, the steering shaft, and the pitman arm, drag link, and knuckle.
- coolant reservoir (conventional): should be secure, not leaking, and filled to the proper level.
- air compressor: should be secure, and not leaking
- power steering pump: should be secure, and not leaking
- power steering hoses: should be secure, and not leaking
- remainder of engine hoses: should be secure, and not leaking
- power steering fluid reservoir: should be secure, not leaking, and filled to the proper lever
- steering gearbox: should be secure, and not leaking
- steering shaft: should be secure, not bent or damaged, and properly greased
- pitman arm, drag link, and knuckle: should be secure, not bent or damaged, and contain no missing bolts or cotter pins
Steer axle
The driver may now proceed to inspect the suspension system, brakes, and wheel on each steer axle. For the inspection of the suspension to be sufficient, the driver must check the shocks, spring mounts, and spring leaves.
- shocks: should be secure, and not leaking
- spring mounts: both the front and back of the spring mounts should be secure, not bent or damaged, should have no missing bolts, and the U-bolts should be present, secure, and have no missing nuts.
- spring leaves: should be secure, and none should be missing or misaligned
The brake system components the driver must then check are the brake hoses, brake chamber, the slack adjuster, the brake drum, and the brake pads.
- brake hoses: should be secure, and not leaking
- brake chamber: should be secure, not leaking, and not have any cracks or dents
- slack adjusters: should be secure, not cracked or damaged, and not contain more than 1 inch of free play while the brakes are released
- brake drum: shouldn't have any dirt, oil, grease, heat cracks or dents on it
- brake pads: should be at least ¼ inch thick and without any dirt, oil, or grease
Now the driver must inspect the wheel on the steer axle. The driver should first check the inside and outside of the tire to make sure it has no abrasions, bulges, or cuts. The treads on this tire should have a depth of no less than 4/32 of an inch, and the driver should check the air pressure with either a mallet or an air pressure gauge to make sure it is at the proper level. The driver should then check the inside and outside of the rims while keeping a watchful eye out for any cracks or illegal welds that might be present. The driver should check to make sure all of the lug nuts are present and secure-a good indication one might be loose is if streaks of rust are found on the interior of the rim. Finally, before moving to the left side of the tractor, the driver should check the hub to make sure it's secure, not leaking, filled to the proper level, and that the hub seal is also secure and not leaking. The driver should repeat this procedure while inspecting the opposite side of the tractor.
Left side of tractor
The driver should then stand and look at the lights and reflectors on the top and bottom of the left side of the tractor and also the window, the side mirror, the door, the side door box, and the fuel tank.
- lights and reflectors (top and bottom): should be clean, and not cracked or broken
- window: should be clean, and not cracked or broken
- side mirror: should be secure, clean, and not cracked or broken
- door: should open and close properly, it's hinges should be secure, not damaged, properly greased, and its weather stripping should be intact.
- side door box: should open and close properly and should always contain three things:
- three red reflective triangles
- one fully charged 10lb BC fire extinguisher
- fuses (if the vehicle is not equipped with circuit breakers)
- fuel tank: should be secure, and not leaking
Big U
The driver is now ready to move on to inspect the "Big U" of the truck. The term "Big U" refers to the back of the tractor, the front of the trailer, and the length of the frame of the truck before it reaches the fifth wheel. It includes lights and reflectors, the exhaust system, the airline connections at the back of the cab of the tractor, the electrical connections at the back of the cab, the battery box, the catwalk, the frame, the drive shaft, the header board, the glad-hands connections at the trailer, and the electrical connections at the trailer.
- lights and reflectors (back of tractor, top and bottom): should be clean, and not cracked or broken
- exhaust system: should be secure, and not leaking
- airline connections to the tractor: should be secure, and not leaking
- electrical connections to the tractor: should be secure, and plugged in all the way
- battery box: should be secure to the frame--if opened, the battery itself should be secure and not leaking, in the upright position, filled to the proper level, and the contacts should be tight and without frayed wires or signs of corrosion
- catwalk: should be secure, and clean and free of debris
- frame: should be secure, not bent or damaged, and have no missing bolts
- drive shaft: should be secure, not bent or damaged, and properly greased
- headerboard: should be carefully checked for any bulges that might indicate there has been a shift of freight
- glad hands connections to the trailer: should be secure, and not leaking
- electrical connections to the trailer: should be secure, and plugged in all the way
Coupling and rear of tractor
The driver should now inspect the actual coupling of the tractor and the trailer. First the driver should look to make certain there is no gap between the apron and the fifth wheel and that the fifth wheel itself is properly greased, and also that the fifth wheel platform is secure, not bent or damaged, and the mounting bolts are all present and secure. The release arm should be down with the safety latch over it, and the fifth wheel slide locking pins should be out. Now the driver must duck beneath the trailer and inspect the rear end of the tractor even more closely, making sure that the locking jaws are secured around the shank of the kingpin rather than the head, and that the kingpin itself isn't bent or damaged. While the driver is still directly behind the tractor he may wish to take the opportunity to check the rear tractor lights to make sure they're clean and not cracked or broken, and that the splash guards are secure and at the proper height which should be no more than 6 inches from the ground.
Drive Axle
The driver may now proceed to inspect the suspension system, brakes, and wheel on each drive axle. For the inspection of the suspension to be sufficient, the driver must check the shocks, the airbags, the spring mounts, the spring leaves, and the torque arm.
- shocks: should be secure, and not leaking
- airbags: should be secure, and not leaking
- spring mounts: both the front and back of the spring mounts should be secure, not bent or damaged, should have no missing bolts, and the U-bolts should be present, secure, and have no missing nuts.
- spring leaves: should be secure, and none should be missing or misaligned
- torque arm: should be secure, and not bent or damaged
The brake system components the driver must then check are the brake hoses, brake chamber, the slack adjuster, the brake drum, and the brake pads.
- brake hoses: should be secure, and not leaking
- brake chamber: should be secure, not leaking, and not have any cracks or dents
- slack adjusters: should be secure, not cracked or damaged, and not contain more than 1 inch of free play while the brakes are released
- brake drum: shouldn't have any dirt, oil, grease, heat cracks or dents on it
- brake pads: should be at least ¼ inch thick and without any dirt, oil, or grease
Now the driver must inspect the wheels on all of the drive axles. The driver should first check the inside and outside of both tires to make sure they have no abrasions, bulges, or cuts. The treads on these tires should have a depth of no less than 2/32 of an inch, and the driver should check the air pressure with either a mallet or an air pressure gauge to make sure it is at the proper level. The driver should make sure that both of the rims are tightly butted together and clean and free of debris. He must then check the inside and outside of the rims while keeping a watchful eye out for any cracks or illegal welds that might be present. The driver should check to make sure all of the lug nuts are present and secure-a good indication one might be loose is if streaks of rust are found on the interior of the rim. Finally, before moving to the trailer axle, the driver should check the hub to make sure it's secure and not leaking.
Trailer Axle
The driver may now proceed to inspect the suspension system, brakes, and wheel on each drive axle. For the inspection of the suspension to be sufficient, the driver must check the shocks, the airbags, the spring mounts, the spring leaves, the torque arm, and the sliding tandem, if applicable.
- shocks: should be secure, and not leaking
- airbags: should be secure, and not leaking
- spring mounts: both the front and back of the spring mounts should be secure, not bent or damaged, should have no missing bolts, and the U-bolts should be present, secure, and have no missing nuts. The spring mounts on the trailer axle must be welded securely to the frame.
- spring leaves: should be secure, and none should be missing or misaligned
- torque arm: should be secure, and not bent or damaged
If the truck is equipped with a sliding tandem, the tandem release bar should be down, the safety latch should be over it, and the locking pins should be out.
The brake system components the driver must then check are the brake hoses, brake chamber, the slack adjuster, the brake drum, and the brake pads.
- brake hoses: should be secure, and not leaking
- brake chamber: should be secure, not leaking, and not have any cracks or dents
- slack adjusters: should be secure, not cracked or damaged, and not contain more than 1 inch of free play while the brakes are released
- brake drum: shouldn't have any dirt, oil, grease, heat cracks or dents on it
- brake pads: should be at least ¼ inch thick and without any dirt, oil, or grease
Now the driver must inspect the wheels on all of the trailer's axles. The driver should first check the inside and outside of both tires to make sure they have no abrasions, bulges, or cuts. The treads on these tires should have a depth of no less than 2/32 of an inch, and the driver should check the air pressure with either a mallet or an air pressure gauge to make sure it is at the proper level. The driver should make sure the rims are tightly butted together and clean and free of debris. He must then check the inside and outside of both of the rims while keeping a watchful eye out for any cracks or illegal welds that might be present. The driver should check to make sure all of the lug nuts are present and secure-a good indication one might be loose is if streaks of rust are found on the interior of the rim. Finally, before moving to the side of the trailer, the driver should check the hub to make sure it's secure, not leaking, filled to the proper level, and that the hub seal is also secure and not leaking.
Sides of trailer
On the sides of the trailer a good driver will inspect the lights and reflectors, the landing gear, the cross beams, the trailer's splash guards, and the ties.
- lights and reflectors: should be clean, and not cracked or broken
- landing gear: should be all the way up, and the handle should be in the stowed position
- cross beams: should be secure, and not bent, broken, or damaged
- splash guards: should be secure, and elevated to the proper height which is no more than six inches from the ground
- ties: should be secure, and not damaged
Back of the trailer
The driver is now ready to proceed to the back of the trailer where he must inspect the lights and reflectors, the doors, and the DOT bumper.
- lights and reflectors (top and bottom): should be clean, and not cracked or broken
- doors: should open and close properly, hinges should be secure and not damaged, and the locks should also be secure and in the locked position, also free of damage
- DOT bumper: should be secure, not bent or damaged, and have an unmarred strip of conspicuity tape across it
Inside Cab
After completing the inspection of the outside of the truck, the driver is ready to check the truck's interior in an equally meticulous manner. The first thing the driver should do after getting into the driver's seat is turn the tractor's engine on. Then the driver should buckle his seatbelt, noting any frays or damage to the belt and making sure it latches properly. He then should glance into the side mirrors to make certain they are adjusted properly to him, and check to make sure the windshield is clean, not cracked or broken, and bearing no illegal stickers on its surface. He is now ready to move down to the dashboard where he should then check to make sure that the needles on oil gauge, the volts gauge, and the water gauge all fall in the proper operating range, that the windshield wipers work properly and that the windshield wiper fluid reservoir is dispensing fluid when prompted. The driver should check to make sure that both the heater and defroster are operating properly by turning both on and placing a hand above and below the dashboard to make sure the expelled air is the correct temperature. The driver should then turn the steering wheel to make sure it has no more than 10 degrees of free play, check that both the city horn and the air horn emit sound, and that the indicators are working properly. To check the indicators the driver must turn on the dashboard lights and make sure the indicator arrows correctly signal left, right and 4-way, and that the high and low beam headlight indicators also work. The driver is now ready to do a pedal check, and should push the clutch to the floor and more the shifter handle through the first five gears to make sure the clutch is working properly, and then depress the brake pedal and the fuel pedal to make sure they too are operating properly. The driver is now prepared to perform his parking and trailer brake tests.
Brake tests
- parking brake test: driver should push in his trailer brake button, put his truck in low gear, tug gently against his tractor, and pull out the tractor brake button
- trailer brake test: driver should push in the tractor brake button, put his truck in low gear, tug gently against his trailer, and pull out the tractor brake button
In order to check his air brakes, a driver must first set up the truck by turning it off, turning the key on, and pushing in both the tractor and the trailer brake buttons.
- air brake check #1: the first air brake test is to determine the air leakage rate, and the driver performs this test by depressing the brake pedal and making sure that no more than 4 pounds of air pressure are lost within one minute
- air brake check #2: the second air brake test is administered to determine if the air pressure warning light and/or buzzer is working properly-driver should pump the brake pedal, and ideally the buzzer should come on before the pressure level reaches 60 psi
- air brake check #3: this test is sometimes referred to as the "pop-out test"-the driver should continue to pump his brakes-if all is well both the tractor and the trailer brake buttons should pop out somewhere between 20 and 40 psi-this test is administered to determine whether the spring brakes would engage if too much air pressure was lost from the air brakes to make them work properly
Outside light checks
The final element of a tractor trailer a driver should inspect is his outside lights. In order to do this, he must restart the truck. It would be ideal for the driver to have assistance with this portion of the inspection, but if no one is available, he must simply get out of the truck and perform the inspection himself, however tedious it may be. While inspecting the outside lights, the driver must make sure that the following are operating properly:
- left turn signals
- low beam headlights
- right turn signals
- high beam headlights
- 4-way flashers
- taillights
- marker lights
- rear brake lights
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