About 15 years ago Goodyear introduced a - what I call - hybrid 16" trailer tire known as the G614. It had a LT prefix and was dubbed RST for Regional Service Trailer. It had/has a maximum load capacity of 3750# @ 110 PSI.
Not long after the G614 became a very successful replacement tire, the "off shore" tire manufacturer's jumped on-board and started building their brand that mimicked the G614.
With RV trailers getting larger & larger the "off shore" people developed newer ST designs with load capacities suited for the 7000# & 8000# axles on the largest RV trailers.
Not to be outdone, Carlisle has now introduced their 16" LRG all steel tire line-up with the two most popular sizes.
https://www.carlislebrandtires.com/o...-detail/csl-16
I'm not plugging the brand, I have never used Carlisle tires on my RV trailer. However, Carlisle is popular with many on this forum so I've posted their info in the reference above.
Looking back, you'll find that Carlisle was one of the first trailer tire builders that foresaw the need for more load capacity for the 6500# - 7000# axles and developed 16" LRE & LRF ST tire sizes to meet the needs. Their ST235/85R16E has a load capacity of 3640# @ 80 PSI and the same tire in a LRF has a 3960# load capacity @ 95 PSI.
For a long time Carlisle recommended a speed limit of 60 MPH for their trailer tire line-up. Today, all of their Radial trailer tires are rated at 75 MPH or higher.