Semi-trucks are equipped with jaws that come in contact with the kingpin located beneath the trailers. Locking of jaws and trailer kingpin ensures the secure connection between the truck and trailer. They do not need a hitch for towing purposes.
How Do Semi-Trucks Connect To Trailers? You can connect the semi-truck to a trailer by positioning its tires. Lower the landing gears and slowly move backward so jaws come in contact with the kingpin. Engage the parking brake to restrict truck movement and ensure the locking of jaws with a flashlight. Attach the airlines and connectors and go for a test drive.
Semi-trucks and trailers are of different sizes, and it is necessary to check their size compatibility before the procedure. In addition, their size can also be different because of the tires that are mounted with trucks.
How do you connect a semi-truck to a trailer?
Connecting the semi-truck with the trailer is easy, and you do not need a hitch for their towing. These structures contain the kingpin and jaws for their secure connection. Moreover, these are easy to tow and unhook. You require less than 5 minutes to complete the procedure, depending on your skills and experience.
Position your truck
You have to correctly position your semi-truck and the trailer. Park these on the leveled ground surface and engage the parking brakes to avoid the back-and-forth motion of the wheels.
However, many people prefer to use wheel blockers to restrict their movement. Move around your vehicles to check the ground clearance and obstacles.
Align your trucks in front of the trailers so skid plates come in contact with kingpins correctly. Use the side view mirrors to adjust its position.
Crank the landing gears down to adjust its height according to the truck. You have to adjust their height to secure their connection.
Move your truck backward
Engage the drive mode of the truck and slightly move backward. You can get the back view by using side-view mirrors for their proper connection.
Moreover, you can also get help from friends while moving backward. Some modern vehicles have backup cameras, and you can get images on the touch screen.
These cameras make the reversing and trailer attachment process easy. Skid plates come in contact with kingpins during backward movement.
Stop moving when you can hear the click sound because it shows the engagement of the locking mechanism. Use the flashlight to ensure the skid plates and kingpins are locked.
Crank the landing gear
It is necessary to raise the landing gears after completing the procedure. You cannot drive your vehicle with the landing gears because these can disturb the stability and increase the risk of wear and tear.
Moreover, these can also be produced when you try to move forward without raising them.
The crank handle is located on the side of the trailer, and move this to close these height adjustment landing gears.
Connect the service line and electric connectors
You have to connect the service lines, airlines, and electric connectors after hooking up the trailers. These components are tucked on the backside of the semi-truck.
Step on the catwalk area and connect the airlines with trailers at their designated points. Grab the electric connectors or pigtails and hook these to their specific location.
Electric connectors are known as pigtails because of their pig-like noses. Ensure the brake light, trailer light, and brakes are properly functioning before driving.
Move inside your truck, turn on the ignition, disengage the parking brakes, and move forward for a test drive.
Things to consider while connecting trailers with semi trucks
You should check the skid plate of the semi-truck and ensure it is free from damage and cracks. These cannot fit inside the kingpin if slightly bent or damaged.
In addition, clean the skid plate before mounting these. It is also better to grease the kingpin and skid plate to ensure their smooth latching mechanism.
Positioning the truck in front of the trailer is essential for their correct mounting. Kingpin cannot come inside the skid plates when these are not positioned correctly.
Read the manual and the safety precautions to ensure safety while performing this procedure. You should ensure that your mounting vehicle is also free from damages and malfunctioning that can cause issues during their operation.
Close the landing gears before moving because these can cause stability issues and damage. Ensure the proper connections of airlines and electric connectors because poor electric connections affect the functioning of trailer lights.
Moreover, park both vehicles at the leveled ground surface and ensure the proper ground clearance. Maintain the distance between these vehicles while doing the procedure to reduce the risk of collision.
Connecting your vehicle with loaded trailers to improve stability during the procedure is better. However, it is necessary to ensure that cargo is evenly distributed on the bed.
Use the landing gear to adjust the height of the trailer according to the fifth wheel. I also consider weather conditions while doing this because adverse weather can affect driving conditions.
Why would you connect a semi-truck with a trailer?
Semi-trucks are larger and usually contain 18 wheels. These are designed to haul heavier cargo from one place to another because of their more load-carrying capacity.
Many people connect these vehicles with trailers to increase the cargo capacity. It increases the cargo capacity so you can haul the larger and bulky cargo in one trip.
It also saves the transportation cost required for multiple trips during the transportation procedure. It is an efficient and cost-saving method for the transportation of several materials.
Moreover, they are easy to hook and unhook and require a few minutes.
You can hook these according to the type of material you want to carry. These are specialized for transporting larger containers, liquid materials, live stocks, sand, rocks, and other construction materials.
It also reduces the need for several long-haul trucks and saves your costs. These are also beneficial when there is a shortage of experienced drivers.
You can transport the maximum luggage in a single turn, which helps solve the issue of driver shortages.
How to unhook a trailer from a semi-truck?
Turn off your truck and engage the parking brakes to unhook the trailers from the semi-trucks. Moreover, I prefer using wheel chocks to avoid unnecessary back-and-forth movement during the procedure.
Come out from your vehicle and inspect the surroundings to ensure the ground clearance. Lower the landing gears that are present on the sides to provide stability.
You can see a red color pipe, which is the emergency airline, and you must disconnect it. Push the airline pipe with its handle and release it to remove these from the trailers.
You have to disconnect the pigtails or electric connectors used to turn on the trailer lights to enhance their visibility in low-light conditions.
Remove the service line that is responsible for controlling the braking functions. Properly position the service lines, electric connectors, and airlines on the back side of the semi-truck.
Avoid leaving these on the catwalk because they can fall on the drivetrain, which can cause serious damage. The chances of falling on a train increase while moving on bumpy roads or sudden brakes.
Move towards the trailers, and you can see locking jaws on their lower side. These locking jaws are located adjacent to the skid plates.
Use a flashlight to find the locking jaw and pull it with your hand to release the latch. The locking mechanism disconnects the skid plates and kingpins.
Move towards your trunk and press the yellow button to disengage the parking brake. Put your truck in drive mode and slowly move forward.