Which Wheels and Why
Any change in tire size may require a change in wheel, and a "Plus" conversion will demand it. The wheels you choose may be aluminum (or similar alloy) or steel, with other materials available but rarely DOT/street legal. Whatever wheel you choose, the following must be considered.
Size: Does it have the right offset and backspacing for your truck? If it doesn't, it may make the tire contact the bodywork at extremes of steering lock and/or suspension travel and may wear out wheel bearings and bushings much faster.
Clearance: Does the wheel clear the brake caliper or drum, including interference caused by wheel weights? More than one truck has gone unbalanced as it left the shop with the brake caliper scraping off the balance weights. Tire clearance should be checked at full steering lock and full range of suspension travel. Check in back, too, as a crossed-up solid axle will sometimes make an oversize tire rub on the inside wheelwell.
Lug nuts (or bolts): Aluminum wheels are normally thicker than steel wheels and therefore may need a longer wheel stud or bolt. The type of lug nut (conical, shank, flat, etc.) may also vary by wheel. If you purchase four new wheels (because you were cheap or the new tire won't fit in the spare well), be sure to keep whatever bolts/lugs you need for the spare in case of a flat. Lug-nut torque is often different for aluminum or steel wheels, dual wheels sometimes have higher torque specifications, and aluminum wheels in particular should be retorqued a hundred or so miles after installation.
Valve stems: Expensive cars come with metal valve stems, and many people add them with new-wheel purchases. Metal stems rarely rot like rubber, but they do not bend either, so if your wheels often encounter downed tree branches, offensive rocks, or chunks of ice and snow, rubber stems will yield and may be better in the long run.
Multipiece: Two- and three-piece wheels are popular for high-performance cars, but they aren't recommended for applications with tires over 31 in. or 265/75 because of the high rim loadings and weight of the average new SUV or light truck.