Tire Options on Utility Trailer With P185/80R13 Tire Size

Updated 01/28/2013 | Published 01/24/2013

Question:

I recently bought a used utility trailer that has a set of P185.80 r 13 tires on it. There isnt a lot of clearance between the fender and tire and I can see where it has rubbed previously. I know the suspensions is good, but would like to know if there is another option of tire a bit smaller in height, but rated to carry a heavier load?

asked by: Maurice S

Expert Reply:

First, I would try to find a identification tag on the trailer to determine the weight capacity of the trailer and if it list a recommended tire size. This would help you determine the capacity of the tire you will need.

The P185/80R13 size is a passenger tire size. A trailer tire will always have a ST designation before the first number to let you know it is a special trailer design tire. A trailer tire will have stronger sidewalls and normally a higher load capacity compared to a passenger car tire.

The ST185/80D13 trailer tire that I have is a load range D (8-ply rated) tire with a maximum load capacity of 1,725 lbs at 65 psi. This is a bias design tire, not a radial tire.

A smaller ST175/80-13 tire size is available in both a bias tire design and a radial tire design. I would recommend a radial tire as a first choice. This size would be just under a 1/2-inch shorter in height and about 1/4-inch narrower compared to the 185/80-13 tire size.

The Kenda Karrier ST175/80R13 Radial Trailer Tire, part # AM10210, is a load range D (8-ply rated) tire with a maximum load capacity of 1,610 lbs at 65 psi. If you used two of these tires on your axle it would give you a maximum weight capacity of 3,220 lbs on your trailer. This maximum weight capacity would be reduced if you have other parts on the trailer that would have a lower weight capacity.

I am including links to a couple of FAQ articles on trailer tires.

expert reply by: Jeff D