How often should I check the tire pressure on my boat trailer?

You should check your boat trailer tire pressure at least once a month—and more often during heavy use, long trips, or seasonal changes. Here’s why:

• Natural air loss: All tires lose air slowly over time, even when not in use. If your trailer is stored for months at a time, check pressures before every tow.
• Sudden loss: Tires can lose air quickly if you hit a pothole, strike a curb at the launch ramp, or clip debris on the road.
• Visual checks aren’t enough: With radial trailer tires, under-inflation isn’t obvious by sight—you need a gauge to know for sure.
• Cold tire readings: Always measure when the tires are “cold” (sitting for at least three hours). Driving—even just a few miles—heats them up and increases pressure, giving a false reading.

Boat trailer considerations:

• Thicker sidewalls: Trailer tires (ST tires) are built with thicker sidewalls to handle vertical loads. This helps support the boat but also generates more heat if under-inflated. Heat build-up is a leading cause of blowouts.
• Seasonal usage: If your trailer sits idle during the off-season, tires may lose several PSI over winter storage. Always re-check before the first tow of the season, and again throughout the summer when temperatures fluctuate.
• Carrying a gauge: Keep a reliable tire pressure gauge in your tow vehicle or trailer box. Digital or dial gauges are more accurate than pencil-style ones.

Pro Tip: Inflate trailer tires to the maximum cold PSI shown on the sidewall unless you know the exact load weight and have a manufacturer-specific pressure chart. This ensures the tire can carry the rated load safely and reduces the risk of heat build-up.