wintersun wrote:
. . .If the sidewall on the rear tire states a max load of 3200@80 PSI then the total load is 6400 lbs. minus the 3000-3300 lb. weight of the truck. . .
This is confusing. The proper term would be GVWR or gross vehicle weight rating - not "total load", right?
When a truck tire goes over a curb or hits a pothole, it can cause a single tire to support the entire payload.
This is frequently the case with dually trucks when a low curb lifts the truck by the rear outside wheel and leaves the inner tire suspended off the ground.
Looking at the rear tire of a dually one will see that that tire has two ratings!
One rating is lower for use on a dually and the other rating is higher when used on a single wheel.
Confused yet?
Again, the dumb simple straight forward method to determine payload is to look at the tire's printed rating.