How do I check the tire tread on my boat trailer tires?

Checking your tire tread is critical for safe towing. Boat trailers often sit for long periods and are exposed to harsher conditions like water, salt, and UV, which can wear tires differently than passenger vehicles.

• Built-In Wear Bars: Trailer tires have tread wear indicators—raised bars molded into the grooves. When these bars are flush with the tread surface, the tire has reached the end of its safe life and should be replaced.

• Penny Test: Place a penny in the tread with Lincoln’s head facing down. If you can see the top of Lincoln’s head, your tread depth is below 2/32″ and the tire should be replaced.
• Tread Depth Gauge: For more accuracy, use a tread depth gauge. Trailer tires should generally be replaced once tread depth is at or below 3/32″, especially if you tow long distances.
• Even vs. Uneven Wear: Uneven wear on boat trailer tires often points to under-inflation, over-inflation, axle misalignment, or improper loading. Catching this early helps prevent blowouts.
• Age and Environment: Even if your tread looks acceptable, boat trailer tires can age out due to UV exposure and repeated contact with water. Most trailer tires should be replaced every 4–6 years regardless of tread depth. Check for sidewall cracks, dry rot, or bulges in addition to tread wear.

???? Tip for boat trailer owners: Because trailers are frequently dunked at boat ramps, always inspect your tires before and after long trips. Submersion in saltwater, in particular, can accelerate cracking and hidden damage.