Identifying Radial vs Bias Tires

Updated 05/11/2018 | Published 05/10/2018

Products Featured in This Question

Loadstar ST205/75D15 Bias Trailer Tire - Load Range C

(3833)

$79.91

Karrier ST205/75R15 KR03 Radial Trailer Tire - Load Range D

(2281)

$123.60

Question:

how dose one tell the difference between a bias and radial tire?

asked by: Ken

Expert Reply:

The easiest way to tell is by looking at the sidewall of the tire. A lot of times they state bias or radial construction. If not then you can usually tell by the size. If there's a "D" or "B" before the rim diameter, such as 205/75D15 part # AM1ST92, then it's a bias tire. If there's an "R", like 205/75R15 part # AM10245, then it's radial. If the tire is a radial it will always have an "R". If it doesn't have an "R" it may have a "D", "B", or even just a dash in which case it's a bias tire. Don't get this confused with the load range letter which will come after the tire size if it's listed.

If you're trying to recognize between a bias and radial just by the look of the tire you can usually tell by its shape. A radial's section width generally has a flatter or more square look to it than a bias. A bias will be more rounded. This is why radials get better ground contact since the tread has that flatter design

expert reply by: Charles S