https://www.etrailer.com/dept-pg-Tir...d_Range_D.aspx
https://www.etrailer.com/faq-trailer...questions.aspx
https://www.etrailer.com/faq-trailer...ng-tables.aspx

I put the Karrier radial tire on my trailer. I also went to a load range D instead of the original C that was on the trailer when I bought it. The tires I put on are speed rated up to 81 MPH.