In today’s article, we are going to discuss: Can you jackknife a fifth wheel? We will explain what jackknifing a fifth wheel means, and tell you how to prevent any incidents when hauling a fifth wheel.
Can you jackknife a fifth wheel?
Yes, it is entirely possible for a fifth wheel to jackknife, skid or tip over. When a fifth wheel jackknifes, it means that the trailer did not follow the towing vehicle and did not turn properly. The fifth wheel may turn in a different side and nearly touching sides with your car, as you can see in the image below.
As you will see in the table below, there are two types of conditions that increase the probabilities of accidents caused by jackknifing a fifth wheel:
|Conditions that increase jackknifing accidents||Examples|
|Environmental conditions: Any condition that reduces the amount of friction between the tires of a fifth wheel and the asphalt surface.||Slippery roads due to inclement weather conditionsStrong windsRoads with curves or steep slopesUnstable loads on the truck trailer can roll off and cause the vehicle to lose its balanceDebris or other obstacles on the road.|
|Driver errors: Although environmental factors sometimes cause jackknife-related accidents, driver errors also play an important role.||Speeding: Driving at excessive speeds makes all vehicles more difficult to manoeuvre, and trucks are no exception.|
Hard braking: Hard braking (or slamming) can cause the truck’s tires to lock up and slip, which can produce the jackknife effect.
Attempting to correct and straighten: A driver makes a small mistake (such as drifting slightly out of his lane), panics, and turns the wheel sharply in the opposite direction to try to correct the mistake. Sudden steering manoeuvres like this can cause the vehicle to rock and maybe even jackknife.
Not being aware of blind spots: The blind spots of a fifth wheel are much larger than those of a common passenger vehicle, which makes it easier for the surrounding vehicles to disappear completely.
Improper vehicle maintenance: Failure to maintain fifth-wheel components can lead to brake failure and tire blowout, which can cause the truck to jackknife.
What happens when a fifth wheel jackknifes?
Jackknife is produced in most cases by a loss of traction between the fifth wheel tires and the asphalt surface of the road. Instead of sticking to the asphalt as they should, the tires slip without proper traction, making it difficult or impossible for the driver to control them.
When a truck’s cab and trailer are out of sync, the two components can fold toward each other, frequently causing the trailer to swing away from the cab. The rampant trailer can then strike objects in its path or even tip over, causing possible serious injury to other drivers who are in the wrong place at the wrong time.
A fifth wheel or gooseneck trailer is attached to the middle of the tow truck bed. The fifth wheel hitch occupies the centre of the truck bed, which is a major disadvantage.
Jackknifing happens extremely often when new drivers try to back up with their fifth wheel hooked to the car.
Jackknifing can cause serious damage to both your car and fifth wheel, and can also cause serious accidents if the driver panics and doesn’t know how to manage the situation.
Other questions you may be interested in
Safety tips for hauling a fifth-wheel trailer
Hauling a fifth-wheel trailer is not as difficult as other trailers because the hitch pin is in front of the rear axle of the towing vehicle, which creates stability. Safety is not that big of a concern when towing a fifth-wheel trailer, but there are things to keep in mind when hauling any trailer.
- Keep an eye on the weight of the trailer – One thing to consider before towing a trailer is weight distribution. For proper handling, the hitch weight – the amount of weight that is placed on the towing vehicle – must be at least 10 per cent of the total trailer weight. In some cases, it can be up to 15 per cent.
This allows for the best handling ability while hauling the trailer. If the weight is not distributed properly, the driver can lose control of the trailer, causing it to be herringbone or sway back and forth through the lane.
- Safety Balancing – Using a sway control system can help tremendously with towing any trailer. Accidents occur when trailers begin to sway due to a change in load or suspension problems. It is very difficult to control a swaying trailer, but there are two types of sway control systems recommended for hauling: dual cam sway control and friction bar.
The dual-cam control is attached to the trailer spring and accounts for weight and sway changes while allowing the trailer to follow behind the towing vehicle. The bar slides in friction and in accordance with the turns of the vehicle and stops to prevent rocking.
- Learn how to back up a trailer. Accidents often happen when backing up fifth-wheel trailers. The most important thing to remember when backing up a trailer that is on the trailer is that the trailer will move in the opposite direction to what you expect.
Turn the vehicle’s wheels in the opposite direction of how you want the trailer to move. To be safe, you always have someone to help you when backing up. The second person can be behind the trailer to ensure that no collision occurs.
- Safety light brake. Because a vehicle’s lights are hidden when a trailer is pulled, trailers are required to have taillights, brake lights, and license plate lights. Signal lamps are also necessary if your trailer obstructs vehicle signal lights. Make sure you have all of these lights, especially when towing a fifth-wheel trailer at night.
The bottom line
Fifth wheels are best for hauling heavy and exceptionally long trailers. They allow the truck to manoeuvre with ease because the hitch is located inside the cargo box, making it easier to make sharp turns. The hitch is made up of a large horseshoe-shaped plate – the “fifth wheel”.
Whenever hooking up a 5th wheel, please make sure you follow all the safety tips and necessary precautions.
If you have any questions or comments on the content, please let us know.
FAQ on Can you jackknife a fifth wheel?
Can you hook up a 5th wheel on an angle?
Yes, you can hook up a 5th wheel trailer on an angle, as long as you take all the necessary precautions and safety tips. Still, take into consideration that hooking up the trailer at a different angle will take more time and you need to be more thorough with the process.
How does the fifth wheel hitch work?
A fifth wheel hitch l works by locking a kingpin in the lockjaw. The kingpin is similar to a hitch coupler and is attached to the semi-trailer, while the locking jaw acts as the receiver for the hitch
Are gooseneck 5th Wheel Adapters safe?
Gooseneck 5th wheel adapters are safe, but not the best option for permanent use. A fifth wheel hitch is best for recreational towing (e.g for a trip), while a gooseneck hitch is recommended for commercial towing.
What is a fifth wheel hitch?
A fifth wheel hitch is specially designed for the beds of vans and flatbed trucks. With a towing capacity between 5500 and 9000 Kg and a weight capacity between 550 and 770 Kg, 5th wheel hitches are installed just above and above the rear axle of a truck.