The Dodge Ram 2500 diesel is a full-size 3/4-ton pickup truck that has been available in a variety of configurations since 1994. The stock tire size of the Dodge Ram 2500 may vary based on the model year and options that a particular truck is equipped with. Although manufacturers recommend that replacement tires should always be the same size as the stock vehicle tires, various sizes of tires can be installed on a Dodge Ram 2500 for increased performance or a rugged look.
Locate the size of your current tires on the exterior wall of the tire. Tire sizes are specified in a format that spells out the tire's tread width in millimeters, the tire's aspect ratio--or sidewall height as a percentage, and the diameter of wheel that the tire is intended to be mounted on. For example, a 315/75R16 tire is 315 millimeters wide, with a sidewall height 75 percent of the width, and is meant to be mounted on a 16-inch wheel. Off-road style tires may be expressed in a format that uses inches to measure the overall height and width of the tire. Write down this number from the outer wall of your tires as a reference point to select new tires.
Visit a reputable local or online tire distributor to select new tires for your Dodge Ram 2500. Talk to your tire retailer about the largest tire that will fit on your truck without modifications to the wheels or suspension. Most trucks and SUVs are designed to handle an overall 15-percent increase in tire size without major vehicle modification. Choosing a larger tire may require that the vehicle's suspension be lifted in order to allow the tire to turn properly without rubbing on the truck's wheel well.
Purchase a set of four tires in the desired size. It is important that all of the tires on a vehicle are the same size, requiring that you purchase a full set when changing tire size on your Dodge Ram 2500. Work with your tire retailer to have the tires mounted on your wheels and installed on the vehicle.
Visit a tire retailer or automotive repair shop to have your speedometer calibrated for accuracy. Larger or smaller tires than the stock vehicle size will adversely affect the readings of your speedometer and may cause you to think that you are going faster or slower than you actually are. Most newer vehicles control this function through their computers, which most auto shops have the technology to easily reset.
