Can 4.8-8 Trailer Tires Be Replaced with a Larger Size on a Boat Trailer

Question:

I have a boat trailer with 4.80 x 8 tires that need to be replaced. what should I look for to improve tire wear and should I consider a larger tire. They seem so tiny. The boat and motor is probably 350 pounds but I tend to put camping gear in it so maybe 500 pounds towing weight plus the trailer

asked by: Steve G

Expert Reply:

First, you will need to make sure the tire capacity (combined) meets or exceeds the loaded trailer. Any given trailer tire can come in different load ranges which will vary the capacity of that tire. A load range B in 4.80-8 has a capacity of 590 pounds per tire. Going up to a load range C and the capacity increases to 760 pounds per tire.

Avoid overloading the trailer. Make sure you are within the stated capacity (which should be on a sticker or plate somewhere on the trailer frame near the front of the trailer). Have the suspension inspected by a trailer shop. Worn suspension components can cause tire wear.

Always inflate trailer tires to the maximum psi as indicated on the tire. Trailer tires are built with a thicker sidewall to handle more vertical load than passenger vehicle tires. If under inflated, the thicker sidewall will generate more heat quickly and cause the tire to fail.

After launching the boat and, later, putting it back on the trailer, spraying off the tires with clean fresh water can help prevent wear on the sidewalls. When storing the trailer you can also keep the tires covered (if you store it outside).

Going to larger tire is possible but you will have to make sure you have room all around the existing tires for a larger size. The next tire size up for what you have that also fits the same wheels is going to be a 5.70-8 tire. It will be 2 inches taller and 1 inch wider. I have included links to all of the tires and tire and wheel combos in both sizes for you.

I have also included a link to our FAQ article on trailer tires.

expert reply by: Michael H