hi gold, you might want to look into LT215-75-15 D or E's. much more availability from all tire companys. 1/8 inch or 1/4 difference. my 2012 20 foot trailer had st225-75-15D and those were taken off after 30 days and upgraded to LT235-75-15D. they fit ,work and ride better than original. and more tire brand choices for LT 235 for me. ronnie