Replacing 4.80-12 Trailer Tires with a Larger Size on a Harbor Freight Trailer

Question:

My folding HF trailer has 3.75inch rims 4-bolt pattern with 4.80inch X 12inch load rated B tires. I would like to migrate to a tire with a greater load carrying capability. Your recommendations please.

asked by: Stephen H

Expert Reply:

I will be happy to recommend different tires for your trailer. However keep in mind that going to a higher capacity tire does not increase the capacity of the trailer. That is set by the axle and other components.

A 145/80-12 tire would be a good option. Tire # AM10130 is a load range D rated for 1,220 pounds at 65 psi. Always inflate trailer tires to the maximum psi indicated on the tire.

But it will be approximately 0.8 inches wider and 0.8 inches taller than a 4.80-12. You will need to be sure you have the available space all around the tire for the larger size.

You mentioned the wheel width was 3-3/4 inches. This is not a normal size for a 4.80-12 tire. A 3-3/4 inch wheel, measured from bead seat to bead seat, is normally only found on 4.80/4.00-8 and 5.70-8 tires.

If the wheels you have are indeed 3-3/4 inches then I recommend also replacing the wheels with # AM20122 which has a 4 on 4 bolt pattern, takes 1/2 inch-20 studs, and has a center pilot hole diameter of 2.84 inches.

expert reply by: Michael H