Why does my boat trailer bounce or sway when driving?

If your boat trailer bounces or sways on the road, it’s usually a sign of improper weight distribution, suspension issues, or worn components. A stable trailer should track smoothly behind your tow vehicle, so any bouncing or swaying needs to be addressed before it becomes a safety hazard.

Common Causes of Boat Trailer Bouncing

1. Light Tongue Weight

• If too little weight is on the hitch (tongue weight under 5-7% of total trailer weight), the trailer will bounce and lift over bumps.
• Moving the boat slightly forward on the trailer can help correct this.

2. Stiff or Worn Suspension

• Leaf springs or torsion axles that are too stiff for the load will cause a rough, bouncy ride.
• Worn bushings or broken springs can also reduce shock absorption.

3. Overinflated Tires

• Trailer tires inflated beyond the recommended PSI won’t flex enough to absorb bumps, making the trailer hop on rough roads.

4. Improper Load Distribution

• If the boat isn’t centered or balanced correctly, weight may shift unevenly, leading to bounce.

Common Causes of Boat Trailer Sway

1. Too Little Tongue Weight

• Like bouncing, sway often happens when the tongue weight is too light. The trailer starts to fishtail at higher speeds.

2. High Speeds or Crosswinds

• Wind can push a poorly balanced trailer side-to-side, especially at highway speeds

3. Worn Suspension or Axle Misalignment

• Loose, misaligned, or damaged axles can cause sway and poor tracking.

4. Uneven Tire Pressure or Size

• Mismatched or underinflated tires reduce stability and increase sway risk.

Boat trailer bounce and sway usually come down to weight distribution, suspension condition, or tire setup. By making small adjustments—like shifting your boat forward, checking tire pressure, and inspecting your suspension—you can drastically improve towing stability and safety.