What Causes Trailer Sway?

What Causes Trailer Sway?


What Causes Trailer Sway?

Trailer sway, also known as fishtailing, occurs when a towed trailer begins to oscillate side-to-side, leading to a loss of control. Several factors can contribute to trailer sway, and it's crucial to understand and address these factors to ensure safe towing. Here are some common causes of trailer sway:

Improper Weight Distribution

Uneven weight distribution on the trailer can lead to instability. Ensure that the load is evenly distributed, with about 60% of the weight in the front half of the trailer and the remaining 40% in the back.

Incorrect Tongue Weight

The tongue weight is the downward force exerted on the hitch ball by the trailer. Too much or too little tongue weight can contribute to sway. Aim for a tongue weight that is approximately 10-15% of the trailer's total weight.

Wind and Weather Conditions

Strong crosswinds or gusty winds can affect the stability of the trailer. Reduce speed and use caution when driving in windy conditions.

Inadequate Tire Pressure

Incorrect tire pressure, either overinflated or underinflated, can lead to instability. Regularly check and maintain the proper tire pressure for both the tow vehicle and the trailer.

Trailer and Tow Vehicle Mismatch

Ensure that your tow vehicle is appropriately matched to the size and weight of the trailer. Consult the vehicle's towing capacity and use the correct hitch for your setup.

Improperly Loaded Cargo

Securely fasten and balance the cargo in the trailer. Loose or shifting cargo can cause the trailer to sway.

High Speeds

Excessive speeds can exacerbate trailer sway. Always adhere to recommended speed limits, especially when towing.

Sudden Steering Maneuvers

Avoid sudden or sharp steering movements, as they can trigger sway. Make gradual and controlled steering adjustments.

Hitch Issues

Ensure that the hitch is in good condition, properly installed, and adjusted according to the manufacturer's recommendations.

Suspension and Shocks

Worn-out or inadequate suspension components and shocks can contribute to trailer sway. Regularly inspect and maintain the suspension system.

How to Stop Trailer Sway?

If you find yourself dealing with trailer sway while towing, it's important to take immediate and appropriate action to regain control. Here are steps to help you stop trailer sway:

Stay Calm

It's crucial to remain calm and avoid panicking. Maintain a firm grip on the steering wheel and stay focused on regaining control of the trailer.

Do Not Slam on the Brakes

Avoid sudden and aggressive braking, as it can worsen the sway. Instead, apply the brakes gradually and smoothly. If your trailer is equipped with its own brakes, you may use them independently of the tow vehicle's brakes.

Do Not Overcorrect

Resist the urge to make sudden steering adjustments. Overcorrecting can intensify the sway. Make small, gradual steering inputs to bring the trailer back in line.

Reduce Speed Gradually

Slow down gradually by lifting your foot off the accelerator. Avoid sudden deceleration, which can exacerbate the sway.

Shift Weight

If it is safe to do so, consider adjusting the weight distribution within the trailer. Shifting some weight to the front of the trailer can help stabilize it. However, only attempt this if it can be done safely and without causing further issues.

Use Tow Vehicle's Brake Controller

If your tow vehicle is equipped with a brake controller for the trailer, use it to apply the trailer brakes manually. This can help in stabilizing the trailer.

Pull Over Safely

When conditions allow, find a safe place to pull over to the side of the road. Check the trailer's weight distribution, tire pressures, and hitch setup. Make any necessary adjustments before continuing.

Address Underlying Causes

After safely stopping and assessing the situation, address the root causes of the sway. Check the weight distribution, tongue weight, tire pressures, and ensure proper hitch setup.

Consider Anti-Sway Devices

Investing in anti-sway devices, such as sway bars or weight distribution hitches with built-in sway control, can help prevent or minimize trailer sway.

Practice Safe Towing Techniques

Familiarize yourself with safe towing practices, including proper loading, weight distribution, and maintenance of your towing equipment.

Remember that prevention is key, so always follow proper towing guidelines and regularly inspect and maintain your towing setup to minimize the risk of trailer sway. If you're unsure about your towing setup or experience persistent sway issues, consult with a professional or seek advice from your trailer and towing equipment manufacturer.

What is Trailer Sway Control?

Trailer sway control is a technology designed to enhance the stability and safety of towed trailers by mitigating the occurrence of trailer sway, also known as fishtailing. Trailer sway control systems are integrated into some modern vehicles and are also available as aftermarket add-ons. These systems use various sensors and technologies to detect and respond to trailer sway in real-time. Key features of trailer sway control systems include:


These systems typically use sensors, such as accelerometers and gyroscopes, to monitor the movement and stability of both the tow vehicle and the trailer. These sensors detect any lateral movements or oscillations that indicate the onset of trailer sway.

Brake Application

One common method used by trailer sway control systems involves applying the brakes selectively to specific wheels of the tow vehicle and/or the trailer. This helps to counteract the sway by stabilizing the entire towing setup.

Engine Power Adjustment

Some systems may also have the capability to adjust the engine power to counteract trailer sway. By reducing engine power, the system can help bring the towing setup back under control.

Automatic Intervention

Trailer sway control systems operate automatically, and their interventions are often seamless to the driver. When the system detects sway, it responds quickly to apply brakes or adjust engine power without requiring any input from the driver.

Integration with Stability Control

In many cases, trailer sway control is integrated with the vehicle's overall stability control system. This allows for a more comprehensive approach to maintaining stability, not only in the presence of trailer sway but also in various driving conditions.

User Settings

Some systems may offer customizable settings, allowing drivers to adjust the sensitivity or aggressiveness of the trailer sway control based on their preferences or the specific towing conditions.

It's important to note that while trailer sway control systems can be effective in preventing or mitigating trailer sway, they are not a substitute for proper towing practices. Drivers should still adhere to recommended towing guidelines, including proper weight distribution, correct hitch setup, and safe driving speeds.

Trailer sway control is a valuable safety feature, especially for those who tow trailers regularly or in challenging conditions. When purchasing a vehicle or considering aftermarket options, it's advisable to check if trailer sway control is included or available as an option.

How to Use Anti-sway Bars on a Travel Trailer?/h2>

Anti-sway bars, also known as sway control bars or weight distribution bars with built-in sway control, are devices designed to minimize trailer sway and enhance the stability of a travel trailer when towing. Here's a step-by-step guide on how to properly use anti-sway bars on a travel trailer:


Before starting, ensure that your travel trailer is properly hitched to your tow vehicle. Attach the anti-sway bars to the trailer's frame using the provided brackets. These brackets are typically installed near the trailer's coupler.

Ball Mount Installation

Attach the ball mount to your tow vehicle's hitch receiver, ensuring it's properly secured and tightened according to the manufacturer's specifications.

Connect the Anti-Sway Bars to the Ball Mount

The anti-sway bars are equipped with friction or sway control mechanisms. Connect them to the ball mount on the tow vehicle. Some systems use a ball-and-socket connection for easy attachment.

Adjust the Tension

Many anti-sway bar systems have an adjustable tension feature. Adjust the tension based on the specific recommendations provided by the manufacturer. Adequate tension helps ensure that the anti-sway bars effectively control lateral movements without being overly restrictive.


Before hitting the road, perform a short test drive in a controlled area to ensure that the anti-sway bars are functioning correctly. Pay attention to the trailer's stability during turns and maneuvers.

Regular Inspection

Periodically inspect the anti-sway bar system for wear, damage, or any loose components. Lubricate any moving parts according to the manufacturer's guidelines.

Follow Manufacturer Recommendations

Always follow the installation, adjustment, and maintenance instructions provided by the anti-sway bar manufacturer.

Adhering to the manufacturer's guidelines ensures the proper and safe functioning of the anti-sway system.

Drive Safely

While anti-sway bars significantly improve stability, it's crucial to drive responsibly. Avoid abrupt maneuvers, high speeds, and sudden braking, which can contribute to trailer sway.

Consider Additional Measures

Depending on your towing setup, you may also use weight distribution hitches in conjunction with anti-sway bars for added stability.

Remember that anti-sway bars are just one component of a comprehensive towing setup. Proper weight distribution, correct hitch setup, and maintaining the recommended tire pressures are equally important for safe and stable towing. If you're unsure about the installation or adjustment of anti-sway bars, consult with the manufacturer's instructions or seek assistance from a professional.