How to Determine Correct Load Rating for Spare ST205/75-14 Trailer Tire and Wheel

Question:

I have a single-axle boat trailer that carries a 3,500# boat. The existing tires are ST205/75/D14. I need to buy a wheel/tire combo to use as a spare. What might you have that would fit this requirement? What load rating in pounds would be required? Thanks your help.

asked by: Dave S

Expert Reply:

The way you determine the correct load rating for your tires is to ensure their capacity exceeds the GVWR of your trailer. The reason for this is the GVWR is the maximum load your trailer and its cargo (in your case a boat) will be.

The highest capacity ST205/75-14 tire and wheel combos are from Westlake, which are load range D and have a 2,040 lb capacity when inflated to their maximum psi, which is 65.

These Westlake tires and wheels are designed for use on boat trailers and are made from aluminum with a clear coat to ensure rust resistance: Westlake ST205/75R14 Radial Tire w 14" Wheel # 274-000053.

These wheels have a 5 on 4-1/2" bolt pattern so you do need to make sure your trailer has that bolt pattern; if you are unsure of what yours is I have added a link to a help article for you which explains this.

expert reply by: Kyle S