Choosing Between Radial or Bias Ply Tires for Boat Trailer

Updated 11/20/2012 | Published 11/18/2012

Products Featured in This Question

Loadstar ST185/80D13 Bias Trailer Tire with 13" White Wheel - 5 on 4-1/2 - Load Range D

(2699)

$165.67

Karrier ST175/80R13 Radial Trailer Tire with 13" White Wheel - 5 on 4-1/2 - Load Range D

(1556)

$147.57

Question:

why bias instead of radial tires on a boat trailer

asked by: Monte

Expert Reply:

The only instance where we might conceivably recommend a bias ply tire over a radial tire would be for farm or agricultural use where the tire would primarily be used on non-paved surfaces. This is due to the fact that the thicker sidewalls used on bias-ply tires would offer more stability.

For a boat trailer, or any other trailer used on pavement a radial tire is preferable. A radial tire will have a more flexible sidewall, which provides better tread contact with the pavement. Radial tires also do a better job of shedding heat. Since excessive heat is the biggest contributor to premature tire wear and failure, I would highly recommend going with a radial tire if one is available in the size and load range you need.

There is not a radial ST185/80R13 load range D wheel/tire combo available, I would recommend part # AM31985 which is a ST175/80R13 load range D tire on the same wheel. This tire is only .2 of an inch narrower and .3 of an inch less in diameter than the bias-ply wheel/tire combo you referenced, and would work very well for you. The size difference is negligible and would not cause the trailer to ride any differently.

I have linked you to our Trailer Tire FAQ article.

expert reply by: Mike L