Can 4.80-12 Tires be Replaced with ST175/80R13 Tires and Wheels on Trailer

Question:

How much more room would I need to switch from 4.80-12 tires witch look a lil small to like the st175/80r13 tire on a shorlander boat trailer or would this be to much lift

asked by: Brian

Expert Reply:

Switching from a 4.80-12 size tire to an ST175/80R13 is quite a decent jump in size but it really just depends on how much room you currently have available both between the top of the tires and fender and between the side of the tire and trailer frame as to if you can safely make the change.

An ST17580R13 tire will be about 3-1/2 inches larger in diameter/height and 2 inches larger in width than what you have right now. Keep in mind too that only half of these differences (1-3/4 inches for height and 1 inch for width) will actually affect your frame and fender clearances because the other half will sit below the axle and towards the outside of the hub.

You will want to maintain at least 4 inches of clearance between the top of the tire and the fender to allow for suspension travel and 2 inches between the tire and frame. If you determine you still have the needed space then you can switch to the larger tires.

If you decide to go this route a really nice option is the Kenda Karrier with 13" Galvanized Wheel # AM31994 as long as you have a 5 on 4-1/2 inch bolt pattern. This tire features a maximum load of 1,610 pounds at 65 psi and the galvanized wheel will offer superior corrosion resistance.

If you find that you won't have enough space for this type of change another option is a 145/80-12 size tire such as the excellent Kenda Karrier # AM10140. This will allow you to use your existing wheels but still give you a tire that's just over an inch larger in diameter/height and 0.8 of an inch larger in width that your existing set.

I have attached a couple video reviews on the products mentioned that you can also check out.