Difference in Trailer Tire Sizes 225/75-15 and 205/75-15

Updated 08/27/2019 | Published 08/26/2019

Question:

I have a ST 225 75 15D and a ST 205 75r15, why does the height look about the same?, And can these be run on the same trailer? Its the last photo, not the first

asked by: Mary B

Expert Reply:

The reason the height on a ST205/75R15 tire like the Castle Rock Trailer Tire # LHCK301 and a ST225/75D15 tire like the Taskmaster Trailer Tire # TTWSF22515D look about the same is because they are about the same, particularly to the naked eye.

When fully inflated a 205/75-15 tire is 27.1" in diameter and a 225/75-15 tire is 28.3" in diameter, and that difference can be hard to see, especially if one is inflated more than the other.

Your photos did not come through but we always recommend having the size tires on your trailer, and having all four be either radial (preferred) or bias tires. Not doing so can mean the trailer will track poorly which can lead to suspension issues and your tires wearing unevenly so they will need to be replaced more often. Additionally, radial tires run cooler than bias tires and are more flexible so you will see a difference in ride quality with that aspect as well.

I very strongly recommend ensuring all of your trailer tires - including the spare - are the same size. I have added a link to our entire selection of 205/75-15 and 225/75-15 tires and wheels for you to check out, along with a link to a help article on trailer tires which I recommend taking a look at.

expert reply by: Kyle S