Originally Posted by OldCoot
They were passenger car tires, not ST.
Passenger tires can be used on trailers today. Probably 35-40% of all tires found on large bass boat trailers are passenger tires. Regulations for boat trailers are the same as RV trailers. However, using them on RV trailers becomes more difficult because of the passenger tire's lower load carrying capabilities after being derated by about 10% for trailer axle service.