A truck tire size chart can be found at the Tire Rack website. The chart offers a comparison between large and smaller light-duty truck tire sizes.
The chart offers information on tires by diameter as opposed to radial size. For example, tires with a diameter of 31.5 inches are available in sizes 265/70R17, 285/60R18 LT235/85R16, LT265/75R16 and 265/75R16.Even though this chart compares the overall diameter of each tire, that does not necessarily mean that a given will fit a selected truck. To determine that, consult the vehicle's service manual.