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Reading back, I stumbled on the ST 235/85R16 LRG with 4400lbs maxload.
That 4400 is calculated for 65mph, and that means more deflection allowed, wich gives more heatproduction, so in the end warmer inside tire air ( or whatever gascompound ).
A LT tire is calculated in maxload for 99mph, ( some 93) and my 115 degr F I based on LT advice pressure, with reserve of 10% to the real load on tire.
So the ST will get hotter at 50mph at 65 degrF.
But when I calculate pressure for ST, I first degrade maxload by 6 Loadindex-steps, to give them a deflection needed for 99mph. Together with adding reserve of 10 to the determined axleload, maximum reserve with still acceptable comfort and gripp, for TT no bumping.
Found out that system, the tiremakers also use.
Rule of tumb is for every 10kmph/6.5mph different used speed, 1 Loadindex step different.
Higher speed》 lower loadindex.
Lower speed》higher loadindex.
Its all done for the temp of tire rubber, not to go above a critical temp, where it hardens, and beginning cracks are made. Then tge tire in fact is lost, but can take even 3 years before damage builds up that farr that tire blows, or treath seperates, with all the missery that can go with it.
Then that once going over the limits, is long forgotten, and tirebrand or origen ( China Bombs) is blamed.
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