Going from class ST to commercial class tires is moving up about 2-3 rungs in tire class
Know that most all commercial class tires (0.5" dia's) do NOT have a safety bead like the lower class tires.
Meaning that you must keep them aired up, as the tapered bead will come off the rim if too low in PSI during side loadings
Personally, do NOT like ST class tires and my trailers all had them replaced with LT class tires
Plus, ST class tires are mostly rated for a max of 65 MPH. There are some special ST's that are rated a bit higher in speed, but not many
