therock

iTrader: (2)

Here is one such example of the vagueness. Until the required speed has been met? I would think "until the tire fails" or something to that effect.

Speed ratings are based on laboratory tests where the tire is pressed against a large diameter metal drum to reflect its appropriate load, and run at ever increasing speeds (in 6.2 mph steps in 10 minute increments) until the tire's required speed has been met.

therock

iTrader: (2)

OK, I found this link

It makes sense from what I suspected. The tires are tested at their load ratings so an empty truck would afford some head room. Click the experts name link to see his credentials.
Not that I'm going to go out and run @ 125 for more than a minute mind you.

It's just the same way we want to know all we can about Air/Fuel ratios and "How lean can we go", I wanted to know whats up with tires and speed and the scenarios.

AKlowriderZ71

iTrader: (22)

I'd worry more about your driveline ejecting from the truck, than the tires.

PathfinderJr

iTrader: (6)

Well what do you know. It's 10 minutes. My mistake. I've always understood it to be 1 minute. Oh well, learn something new everyday..