[scrubjaysnest]

Originally Posted by Padgett

Had a long post hit backspace and it all went away. In short the Load Range of a tire varies with the section width and the inflation pressure. Inflate a LRE tire to 65 psi and it will have the same load rating as a LRD tire for a 225x75 that would be 2540 lbs

Not necessarily correct, you have to go to the tire manufactures load table for that model tire.

If you want you could graph the pressure vs load and not be far off. 1875 lbs at 44 psi, 2150 at 50, 2540 at 65, and 2830 at 80.

In general a steel wheel is stronger than an aluminum one. Though I have not seen either fail without either impact or extreme overloading (e.g. autocrossing). For a 225 section I'd want a 7" rim though a 6" rim is probably OK.

With a 3124 odds are you have a 5k axle which comes standard with a 6 bolt wheel though I have been thinking about replacing my 3.5k axle with a 5k while keeping the 5 bolt hub so is not for sure and for certain.

Our 2011 has a 6 bolt pattern with the 3500# axle.

Final things: in any trailer tire I would be looking for a nylon cap or overlay, essentially an extra belt to stabilize the tread and as with a new car tire, get it balanced - you probably will not feel an out of balance tire on a trailer from the TV and there is no shock absorber to dampen oscillations. One of mine took 3oz.

Below is a graph of load vs psi for a 225x75. As you can see it is pretty linear.