laknox wrote:
Too much for me. My rules of thumb are:
1. Step up one load rating over the placard, either at delivery of a new trailer, or when you swap out the first set of tires.
2. Stay away from STs whenever possible, no matter the tire size.
3. Always run at max sidewall pressure unless running extremely light (like completely unloaded), then drop 10 lbs.
Works for me.
Lyle
But thats yust what this topic is all about.
What you do is using general rules, wich sometimes are exagerated for the situation , but sometimes even aint enaugh.
Meaning of all this is that you can make those choises 1 to 3 more secure.
Only handed as a tool , you still must keep using your common sense.
I realise the last spreadsheet looks complicated, but the list that now are given by tire-makers are made that simple that they can give dangerous answers for most situations.
If you yust open the spreadsheet and begin at the top and work yourself to the bottom, the list is automatically made and filled in .
Then you see as in the example that there is not one ideal pressure but a range in the pressure in wich comfort and gripp is acceptable and no damage to the tires done.
The higher your maximum speed and the more comfort you want, the narrower that range in pressure will be.
There is nothing wrong with ST tires, its the wrong use of them that gives the problems.
Had myself told that ST tires have lesser profile dept so lesser isolation of the rings that produce the most heat by driving.
And ST tires dont make that many miles mostly, so the profile is enaugh for the miles those tires make.
If you use the system described in this topic to determine new ST tires for your trailer or 5th-wheeler , so more reserve, they can last almost as long as when you put LT tires on them.
