Larger Trailer Tire Recommendation to Replace a 205/75-15

Question:

Yes I had sent a questions a few days ago. About putting larger diameter tires on my horse trailer to raise the whole thing off the ground more. In between the tires is the lowest spot Is that how it is suppose to be. trailer is a 1991 model. The size of the tires on it now is P205/75r15. What is the largest size I could put on? Would I have to get a down ball to hitch up to? Thank you.

asked by: Hannah

Expert Reply:

Your current trailer tire size of 205/75-15 has an overall diameter of 27.1 inches. The next size up would be the size 225-75-15. This tire size has an outer diameter of 28.4 inches. This would give you almost an inch and a half of additional wheel diameter. Based on the picture you submitted you should have enough clearance for this. For a tire in this size you would want the # AM10256.

Since your trailer tire size starts with the letter P that indicates you actually have passenger vehicle tires on your trailer which is not a good idea. You want ST type tires as they are designed with a stronger sidewall to handle the heavier vertical loads that trailers have. Also the higher tire pressure that ST tires require would make for a tire that stands "taller" than a P rated tire that would have a much lower recommended pressure.

You may need to go with a different rise/drop ball mount as your trailer would sit higher. If after you install the tires your trailer sits with the nose pointed down you would need to go with a different ball mount. To see how to pick out a ball mount check out the FAQ article I attached.

expert reply by: Jameson C