What Trailer Tire Size is the Right Replacement for A78-13 Tires

Question:

I need replacement tires. The only number on them is A78-13. They are mounted on a 5-hole 14inch rim. The load range is B, with a maximum load of 1060#. What can you recommend?

asked by: Mary U

Helpful Expert Reply:

By definition an A78-13 tire cannot be mounted on a 14 inch wheel since it is a 13 inch tire. Wheel diameter is tricky. When measuring them you do not actually measure the total height of the wheel so you likely have 13 inch wheels.

A78-13 is an old way of indicating a tire size. The metric equivalent is ST175/80-13. Since you have a 5 lug wheel it is likely a 5 on 4-1/2 inch bolt pattern. You can measure by following the help article I have linked for you.

But if you just need tires you do not need to worry about the bolt pattern. For a 175/80-13 tire that is rated in the same range as your current tires you can use # AM1ST74. It is rated for 1,100 pounds at 35 psi. I have also included a couple of helpful links on trailer tires for you.

expert reply by: Michael H