ST Tire "Plies" Question and a PSI Question

laknox wrote:

BFL13 wrote:
IMO nobody said STs could handle shearing better than LTs. They both need full pressure to be best at that. All anybody said somewhere AFAIK was that STs are built to take more weight for their own size. (snipped)

Actually, since STs don't carry passengers (yes, I know it's legal to do so in a FW, but now many really do?), they get away with inflated load ratings because there is little to no safety margin on them, as there is with LTs.

Lyle

Pretty sure it isn't legal here (confirm if important)

I don't have a dog in the ST vs LT race. I have had a flat tire (puncture) on the trailer (STs) that didn't "show" so I drove for a while (don't know how long) on just the one tire on that side. It held ok. That suggests there is quite a bit of margin. I found it was flat when I did a routine PSI check.

That time would mostly be margin on the static loading. I think the "driving at speed under load" margin which I didn't do much would be a more severe test for sure.

If LTs can do that better, that's good, but at least even with STs your trailer won't collapse to one side on the ground if one tire out of two is all that is holding it up that side (at least for a while!)