Semi-trailers are a vital part of modern transport, and their ability to operate safely and efficiently relies on more than just the truck pulling them. One essential component that often goes unnoticed until it fails is the semi-trailer leg—also known as landing gear or landing legs. These sturdy supports play a crucial role in stabilising trailers when they’re not connected to a truck.
In this article, we explore the purpose of semi-trailer legs, why they matter, and how they contribute to safe transport operations.
Main Functions of Semi-Trailer Legs
Semi-trailer legs are designed to:
- Support the trailer when it’s uncoupled from the truck
- Prevent the trailer from tipping forward
- Provide stability while parked, loaded, or unloaded
- Maintain the correct height for easy reconnection to the prime mover
Without these supports, the front of the trailer would collapse when not attached to the truck, causing dangerous conditions for the load, trailer, and anyone nearby.
Why Are They So Important for Safety?
Safety is one of the biggest reasons these legs are essential. Semi trailer legs help:
- Prevent workplace accidents when loading or unloading
- Stabilise the trailer in uneven or windy environments
- Keep cargo from shifting or falling due to imbalance
- Protect the trailer chassis from stress-related damage
If a trailer were to drop suddenly without leg support, the damage to goods and potential for injury could be significant. Investing in reliable semi trailer legs and maintaining them properly is a simple but critical part of any safety protocol.
Types of Semi-Trailer Legs
There are several types of trailer legs available, depending on operational needs:
- Manual landing legs: Cranked by hand, usually with a two-speed gearbox for ease of use.
- Two-speed gearbox legs: Offer high and low gear for quicker or more forceful operation.
- Hydraulic/powered landing legs: Often used in high-frequency fleets or for heavy-duty applications.
The choice of leg depends on trailer type, frequency of use, and operator preference.
How Semi-Trailer Legs Are Operated
Most trailers are fitted with manual landing gear. These require:
- A crank handle, typically located on the driver’s side
- Two-speed operation, allowing drivers to switch between high-speed (less force, more cranking) and low-speed (more force, fewer turns)
- Clear ground contact with foot pads or stabiliser plates
It’s important to operate the landing gear correctly to avoid jamming or overstraining the legs.
Placement of Semi-Trailer Legs
Semi-trailer legs are mounted:
- Just behind the kingpin—the point where the trailer connects to the truck
- On both sides of the trailer chassis
- Bolted or welded to mounting brackets for maximum strength
Their forward placement is intentional to handle the weight of the trailer’s front section when uncoupled.
Common Issues and Maintenance Tips
While trailer legs are built to be durable, they do require regular maintenance to function properly. Common issues include:
- Stiff or stuck cranking due to lack of lubrication
- Uneven leg deployment, usually from gearbox failure
- Bent or damaged legs from rough terrain or improper use
Maintenance tips:
- Grease moving parts regularly
- Inspect for cracks, rust, or loose bolts
- Replace any worn components before a failure occurs
Closing Thoughts
Semi-trailer legs are simple yet vital components that keep your trailer upright, stable, and safe when not attached to a truck. Without them, transport operations would be riskier, slower, and more hazardous for everyone involved.
Whether you’re a fleet operator or a solo driver, maintaining reliable landing legs is essential for safe and efficient logistics. Always inspect your trailer legs during pre-trip checks and consider investing in quality components that meet your load demands.
