How to Determine What Size Tires Are Needed For Replacements

Updated 09/13/2021 | Published 09/12/2021

Products Featured in This Question

Kenda 4.80-12 Bias Trailer Tire with 12" White Wheel - 5 on 4-1/2 - Load Range C

(7907)

$103.58

Kenda Karrier S-Trail ST145/R12 Radial Trailer Tire - Load Range E

(619)

$79.67

Question:

I bought a coverted tilt to boat trailer, single axle, 1,350 weight. The tires are spares for a car, any idea how to figure out the right size?

asked by: Joe

Expert Reply:

Finding the correct tire for your trailer will actually not be difficult at all. This is due to vehicle tires using mostly the same measuring system as trailer tires. There are a few that will not carry over, like the 4.80-12 tire on the Kenda 4.80-12 Bias Trailer Tire with 12" White Wheel # AM30660. but even this will be easy to find a replacement for.

With all that being said, if there is no numbers/letters on the side of your current tires, like 4.80-12 or 145/80R12 as examples, you will need to measure them to confirm the size. I included several help articles we have that will make this easy to do, but essentially all you will need to do is measure the width, side wall height, and diameter of the wheel. These 3 measurements will get you most of the way to the correct tire.

The last thing you will need to do is determine what Load Range you will need for the tire. With your trailer weighing 1,350 pounds, something like the Kenda Karrier S-Trail ST145/R12 Radial Trailer Tire # AM10140 will have a load range E, which means it can handle up to 1,520 pounds at 80 psi. This will be a little higher than needed, but wont negatively affect anything either.

expert reply by: Lazer S