10-17-2025, 04:53 PM
Quick Answer
To check torsion springs on a trailer, observe suspension response under load, inspect arm alignment, and test bounce by jumping on the deck. If the trailer doesn’t flex or rebounds poorly, the springs may be worn or seized.
Torsion Spring Suspension Overview
Torsion springs are a common suspension system in light and medium-duty trailers, including utility, equipment, and enclosed cargo models. Unlike leaf springs, torsion systems use rubber cords or steel bars inside a square axle tube. As the wheel moves, the torsion bar twists, absorbing shock and maintaining ride height.
Manufacturers like Dexter and AL-KO have produced millions of torsion axles since the 1960s, with widespread use in trailers under 10,000 lbs. Their compact design eliminates the need for shackles or hangers, making them ideal for low-profile builds.
Signs of Torsion Spring Wear or Failure
In Maine, a landscaper noticed his trailer bouncing excessively over gravel. After jumping on the deck and finding no rebound, he measured the arm angles and found a 7° difference. Replacing the axle restored ride quality and improved tire wear. He now checks torsion response every spring before hauling equipment.
Preventive Measures
Checking torsion springs on a trailer doesn’t require special tools—just observation, measurement, and a bit of bounce testing. Recognizing early signs of wear can prevent costly breakdowns and improve towing safety. With proper inspection and timely replacement, torsion suspension systems can deliver years of reliable service.
To check torsion springs on a trailer, observe suspension response under load, inspect arm alignment, and test bounce by jumping on the deck. If the trailer doesn’t flex or rebounds poorly, the springs may be worn or seized.
Torsion Spring Suspension Overview
Torsion springs are a common suspension system in light and medium-duty trailers, including utility, equipment, and enclosed cargo models. Unlike leaf springs, torsion systems use rubber cords or steel bars inside a square axle tube. As the wheel moves, the torsion bar twists, absorbing shock and maintaining ride height.
Manufacturers like Dexter and AL-KO have produced millions of torsion axles since the 1960s, with widespread use in trailers under 10,000 lbs. Their compact design eliminates the need for shackles or hangers, making them ideal for low-profile builds.
Signs of Torsion Spring Wear or Failure
- Reduced Suspension Travel
If the trailer feels rigid or bottoms out easily, the torsion bar may be seized or the rubber cords degraded.
- Uneven Ride Height
One side sitting lower than the other suggests internal wear or misalignment.
- No Bounce When Jumped On
A simple field test is to jump on the trailer deck. If it doesn’t flex or rebound, the torsion system may be compromised.
- Cracked or Deformed Axle Tube
Visual signs of damage around the torsion arm or axle housing indicate structural failure.
- Visual Check
Look for rust, cracks, or deformation near the torsion arm and axle tube. Check mounting bolts and welds.
- Bounce Test
Stand on the deck above each wheel and jump. A healthy torsion spring should compress slightly and rebound.
- Arm Angle Measurement
Measure the angle of the torsion arm relative to the frame. Compare both sides. A difference greater than 5° may indicate internal failure.
- Load Simulation
Use a jack to compress the suspension and observe movement. If the arm doesn’t rotate or the wheel doesn’t rise smoothly, the torsion bar may be seized.
- Age and Fatigue
Rubber cords degrade over time, especially in humid or salty environments.
- Overloading
Exceeding axle rating causes permanent deformation and loss of elasticity.
- Impact Damage
Hitting curbs or potholes can shear internal components.
- Water Intrusion
Moisture inside the axle tube accelerates corrosion and rubber breakdown.
- Replace Entire Axle
Most torsion axles are sealed and non-serviceable. Replacement is the standard solution.
- Upgrade to Leaf Spring Suspension
In high-use or off-road applications, switching to leaf springs may offer better durability and serviceability.
- Install Shock Absorbers
Some torsion systems can be retrofitted with shocks to improve damping and reduce wear.
In Maine, a landscaper noticed his trailer bouncing excessively over gravel. After jumping on the deck and finding no rebound, he measured the arm angles and found a 7° difference. Replacing the axle restored ride quality and improved tire wear. He now checks torsion response every spring before hauling equipment.
Preventive Measures
- Inspect torsion arms annually for angle and movement.
- Avoid overloading beyond axle rating.
- Store trailers on level ground to prevent uneven stress.
- Use axle boots or covers to reduce water intrusion.
- Replace axles every 10–12 years in high-use environments.
Checking torsion springs on a trailer doesn’t require special tools—just observation, measurement, and a bit of bounce testing. Recognizing early signs of wear can prevent costly breakdowns and improve towing safety. With proper inspection and timely replacement, torsion suspension systems can deliver years of reliable service.
