Just checked it does say trailer
tires on the door sheet size is "B75x14 b" The Tire shop said the replacements "st205/75r14 b" would be the modern equivalent. We now have St205/75r14 c rated radial
tires they can handle more
weight but not needed. Radial was an option you can still purchase non radial trailer tires if wanted the price is only marginally lower though.
There is no ST on the door for original tires on our 78
boler, sorry just as slip as it does say trailer tires and b rating. There is no law that I know of on Lt vs car vs trailer tires or bias ply vs radial for towing so we each have to find our own way and play safe.
Just feel personally that the specialty tires in radials are a good idea or they would not make them.
P.S. in Ontario the MTO does give car tires a 10% reduction on load limit when on a trailer so it is good to keep this in mind while making a tire selection so as to meet the total load limit needed.
LT, RV and car tires are different than ST tires I do trust company's like Goodyear tire
The sicker inside our
boler trailer says 30/32 psi 30 empty and 32 loaded but also says more maybe needed for heavier loads and to adjust as needed.