How much weight your vehicle can carry is an important part of determining the right tires for your car or truck. The service description of the tire size is an indicator of both the speed index and the tire load index. See the graphic below to identify this area of the tire size:
With the tire load index, what you need to pay attention to is making sure you put the same or higher load rating on your vehicle when replacing your tires. The way the numbers work is based on a chart, the “94” in the picture above represents the tire being able to handle a 1,500 lb. load; with 4 tires that means the load capacity of the vehicle is 6,000 lbs.
So if your tire has a “94” load index, you can replace it with a “94”, “95”, etc.; however you would not put a 93 or lower load index on your vehicle, as the tires would not be sufficient to handle the load capacity of the vehicle.
I could put a fancy chart in here that shows all the load indexes, but it’s huge and really not what’s important to know about this area of the tire size. The most important thing to know your buying new tires is to make sure they have the same or higher index rating, otherwise your tires won’t be able to handle the load.