yes, ST hasn't been updated in a long time. and for trailer tires with only an ST rating, it is a pretty minimal test compared to car/truck tires.
However what is an open question (at least to me) is the current crop of "ST" tires like the goodyear endurance that carry a passenger car/light truck speed rating as well. To meet the speed rating requirements it seems they would need to run the endurance test at the rated speed and load like any other car/light truck tire would need to be run through for the same speed rating.
Goodyear endurance carries a speed rating for something like 85mph IIRC at full rated tire capacity.
and the chart shown by the OP doesn't show the test sequence for ST tires with a load range of C, D, or E. Or for ST tires with a speed rating of 65mph, It just starts with Load range F and speed rating of 50mph. It would be interesting to see the test sequence for ST tires with C, D, or E load range with a speed rating of 65mph like the vast majority of ST trailer tires.
It look like the chart is more aimed at tires used for mobile home tires etc.
