Tire Size – Knowing Which is Which
Knowing your tire size is one of the few things you should learn as a vehicle owner. Tires are parts of your vehicle that have to be replaced every so often, and knowing what size you need saves you a lot of trouble. This also helps in case you decide to change tires depending on the function and performance you need.
Here are the special letters you need to check on to determine the tire’s service type:
If a tire size begins with a ‘P’, it means that this was designed for passenger vehicles and uses the P-metric size. They are the most common kind, used for cars, minivans, SUVs and light pickup trucks.
Tire sizes that do not have any letter preceding it means that it uses the metric size, also called Euro Metric as they are more often used in European cars. They are used in vans and SUVs and have the same sizes as the P-metric tires, with slight differences on load capacity.
Tire sizes that start with a ‘T’ is used for temporary spare tires and are only for temporary use until the original tires have been repaired or replaced with new ones.
Tire sizes that begin with ‘LT’ mean that they use Light Truck metric and are for vehicles that lift heavy cargo or tow large trailers, usually heavy pickup trucks, SUVs and full size vans.
Tire sizes that end in ‘LT’ are used for Numeric, Wide Base, or Flotation Light Truck sizes that allow heavy cargo with 16.5 inch rims or wider, and allow vehicles to drive over loose dirt or sand. They are used for light, medium or heavy pickup trucks and SUVs.
If a tire size ends with a ‘C’, it is for commercial use and would fit into vans or delivery trucks capable of carrying heavy loads.
Tire sizes that begin with ‘ST’ should not be used on cars, vans and light trucks and are specially designed for boat, car or utility trailers.
Immediately following these letters are a set of numbers that stand for the section width of the tire. Seeing a tire size that starts with a P225 for example, would mean that this is a P-metric size tire that measures 225mm across.
There are other codes used in differentiating each tire size from the others, and consulting a professional would help you narrow down your choices and see what your vehicle really needs.