[redstang423]

Greygoose, you should still inflate tires, regardless of any weight classifactions (assuming appropriate for your vehicle), to the car manufacturer's recommended pressures. Pressure is equal to force over area. The force would be the weight of the car seen by each wheel, leaving pressure to control the area, or contact patch of the tire. Automakers do significant testing to figure out what the best settings for that particular vehicle would be, factoring in everything from comfort to safety (proper amount of contact area) to tread wear of the stock sized (in terms of dimensions) tire. While you are free to fill to whatever pressure suits your fancy, departing too much from the recommendations can throw off the handling and safety characteristics of your vehicle. Its very similar to why when Escalades first came out with its small (on a relative scale) wheels and people started putting 22" wheels on it, Cadillac discouraged it since it would alter the inteded handling characteristics of the vehicle, possibly making it unsafe.