Wheel Compatibility for Switching Trailer Tire Size from ST185/80/13R to ST175/80/13

Question:

I am looking to replace my ST tires on my travel trailer. My current tires are ST185/80/13R. Can I change to ST 175/80/13 without having to change the wheel size? May be a dumb question, sorry. I would just like to buy the radial tire, not the bias if possible.

asked by: Beverly E

Expert Reply:

The two trailer tire sizes you mentioned, ST185/80/13R and ST175/80/13R, are close enough in size that they both fit on the same wheel sizes. Both tires fit 13-inch wheels that have width of 4-1/2, 5 or 5-1/2-inches and their overall diameters are close too, differing by only 3/10ths of an inch. You'll have no issue switching to the slightly smaller 175mm size tires.

I suggest the Kenda load range D tire # AM10210. This radial offers a D load range, meaning each one can handle up to 1,610-lbs at their rated 65-psi inflation pressure, and this tire also has an "M" speed rating, meaning it is good to 81-mph.

An easy step to take to keep your trailer tires in good shape is to protect them from UV exposure whenever possible by using tire covers like # ST7000BK. Covers for your tire size are linked for reference.

Always keep your trailer tires inflated to the maximum COLD psi pressure noted right on the sidewall. It is never appropriate to under- or over-inflate a trailer tire.

expert reply by: Adam R