Switching from 5.30-12 to 175/80-13 Trailer Tires

Updated 10/29/2019 | Published 10/28/2019

Question:

I am rebuilding a boat 1967/fiberglass and trailer 1958/steel. Total weight for the combo is 1,920 lbs. But thats without motor, seats, gas, or gear. The trailer came to me with 5.30 x 12inch wheels with a 4 x 4 bolting pattern, rated for 1,045 lbs. It currently has 8inch between the top of axle and bottom of frame. Distance from tread and bottom of fender is 4. Distance from center of hub to bottom of fender is 14 1/2. Distance from frame to inside tire is approximately 1 to 1.25. All rides well now, but my estimated weight fully loaded is around 2,600-2,700 lbs and I dont see any 12inch rims that will carry that load. Can I go to 13s?

asked by: Hardy

Expert Reply:

Yes, you can safely fit a 175/80-13 tire on your boat trailer. I recommend the Loadstar ST175/80D13 Bias Trailer Tire with 13" Galvanized Wheel part # AM3S130 for replacement as the galvanized wheel will do well to resist corrosion and the total load capacity of 2,720 lbs should be plenty for your needs. This option also provides an 81 speed rating.

The 5.30-12 tire is 22" diameter x 5.6" wide and the 175/80-13 tire is 24" diameter x 6.6 wide. Therefore, you will only lose 1" diameter and 1/2" width bringing you to 3" from the top of the tire to the bottom of the fender and 3/4" from the inside of the tire to the frame so you will be just fine with this new size.

expert reply by: Conner L