Tire Speed Rating Question
I'm posting this here because the speed rating of a tire seems to me to cross all lines/types of vehicles. Reading up on warranty issues/questions just now, I came across the following language ...
Forum Discussion
A tire's load capacity decreases as speeds increase.
Conversely, a tire's load capacity increases as speeds decrease.
But a tire's published load capacity is always at it's rated speed.
Let's say you have a tire with a Q speed rating (99 mph) on your vehicle, and let's say it has a load capacity of 3,042 lbs.
When this tire is traveling less than 99 mph, then it has a load capacity that's actually higher than 3,042 lbs, so you can think of this as your safety cushion - since we aren't told "how much" the load capacity increases at lower speeds.
Tire MFR's only publish load/pressure tables, they don't publish what the load capacity is at speeds below the speed rating.
You can vary air pressure to make the load capacity got up or down, but the speed rating is always a fixed part of the equation.
Conversely, a tire's load capacity increases as speeds decrease.
But a tire's published load capacity is always at it's rated speed.
Let's say you have a tire with a Q speed rating (99 mph) on your vehicle, and let's say it has a load capacity of 3,042 lbs.
When this tire is traveling less than 99 mph, then it has a load capacity that's actually higher than 3,042 lbs, so you can think of this as your safety cushion - since we aren't told "how much" the load capacity increases at lower speeds.
Tire MFR's only publish load/pressure tables, they don't publish what the load capacity is at speeds below the speed rating.
You can vary air pressure to make the load capacity got up or down, but the speed rating is always a fixed part of the equation.
