I run used radials on my utility trailer.
My big 5th has trailer tires load range "E".
The only issue with running automotive / light truck tires on a trailer is side wall stiffness.
Trailer tire side walls are stiffer to help reduce sway and resist a blow out if you "curb" it, on an inside turn.
I ran light truck tires on this;
Usually between 5 and 7k #s loaded.
Hauled it thousands of miles, without issue.