How to Determine The Correct Tire And Wheel Size On A Trailer With 4 Hole Bolt Pattern

Question:

hi i have trailer tire are 4 hole 78/13 range c i like to replace them but i dont know how it fit 4 on 4 or 4 on 5 so please tell me how to get the right one

asked by: Khoa T

Expert Reply:

The bolt pattern you will need is 4 on 4 inches. They do not make a 4 on 5 inch bolt pattern.

The tire size of 78/13 should have a letter in front of the 78 number, like B78-13 or C78-13. The old B78-13 tire size will translate to the current 175/80-13 tire size. The old C78-13 tire size will translate to the current 185/80-13 tire size.

The ST175/80-13 (B78-13) tire size is the more common trailer size. If you have the B78-13 tire size you will want to use the Loadstar ST175/80D13 Bias Trailer Tire with 13 Inch White Wheel - 4 on 4 - Load Range C # AM3S120. This is the the white wheel with the 4 on 4 inch bolt pattern. The ST175/80D13 tire is a Load Range C tire.

The ST185/80-13 (C78-13) tire size is usually on trailer wheels with a 5 on 4-1/2 inch bolt pattern.

I am including links to FAQ pages on tire sizing information and measuring wheel bolt patterns.

expert reply by: Jeff D