P = Passenger car tire
LT = Light Truck tire

The Load range is the weight carrying capacity of the tire. C is around 2500lbs/tire D is around 3000lbs per tire and E is more. Tires with higher laod ratings will be tougher tires, thicker, stiffer sidewalls for example. Loadrange E tires are comonly found on 3/4 and 1ton work trucks, I would not recomend them for a Rodeo. They'll be stiff and ride pretty rough. I have "C" tires on my Amigo, and they ride pretty good, D range tires are ok too. I would also stay away from P rated passenger tires, they aren't really the best choice for a 4000 lb truck. They have weak sidewalls that lead to vague handling, and don't seem to last as well.

Good Luck

Mike W