Originally Posted by tractors1
A fully loaded Casita
17LD does not require 80 psi in the tires
. I know as I had one; normally ran 60 psi as recommended by the tire manufacturer.
Running 80 psi means you have to keep a screwdriver handy as the vibration on the road will unscrew the fasteners holding your benches in place!
This is very good advice. It's not a good idea to always pump your tires
up the the max pressure. A tire that is rated to carry 3,000 lbs at 80 PSI, that is only carrying 1000 lbs, should be run at a lower pressure.
Another consideration is cold inflation pressure vs hot pressure. They can go up in pressure 15 PSI when hot, as in running across the hot desert at highway speeds. So, you start out at 80 PSI (max rated pressure indicated on the tire) and are actually running at about 95 PSI. This means they have almost no flexibility and can rupture from impact or pound your poor trailer to pieces because they are rock hard. Tires
need to flex to give the best traction and handling. Too hard and they will skate over rough surfaces and skid very easily when braking. There seems to be a sort of art to getting the right pressure, but they should not be rock hard or low to where they heat up. Radial tires are designed to have flexible sidewalls and ride smooth, so they can look a bit low even when inflated properly. It's funny that the same person that will inflate their TV tires to 40 psi will inflate the trailer tires to 80 psi and think nothing of it.
One other point is the "ply" rating. Heavy duty tires are not "10 Ply". They are "10 Ply rated". It's marketing. Call them load range E. Most tires today are two or three ply sidewall and about 5 ply tread, regardless of the "Ply" rating. Read the sidewall of your own tires to verify this. They are not "10 Ply" tires.