Tire Load Index Chart: What the Numbers on Your Sidewall Actually Mean

Every tire sold in the United States carries a load index rating stamped right on the sidewall — and most drivers never look at it. That's a problem, because using tires with the wrong load rating can affect handling, tire longevity, and safety, especially when hauling cargo or towing.

What Is a Tire Load Index?

The load index is a two- or three-digit number that represents the maximum weight a single tire can safely support when properly inflated. It's part of the tire's size designation — for example, in 225/65R17 102T, the number 102 is the load index.

The number itself isn't a weight in pounds or kilograms. It's a code that corresponds to a specific weight capacity on a standardized chart. A load index of 102, for instance, corresponds to 1,874 pounds per tire — meaning four of those tires, at full inflation, can support a combined 7,496 pounds.

Standard Tire Load Index Chart

Load index values run from roughly 0 to 150+, with passenger car tires typically falling between 75 and 110, and light truck tires ranging from 100 to 130 or higher.

Where Load Index Appears on the Sidewall

The load index is embedded within the tire's full size marking. Here's how to read it:

P225/65R17 102T

• P — Passenger tire designation
• 225 — Section width in millimeters
• 65 — Aspect ratio (sidewall height as % of width)
• R — Radial construction
• 17 — Wheel diameter in inches
• 102 — Load index
• T — Speed rating

Light truck tires are often marked LT at the beginning or end of the size string and may show two load index numbers — one for single rear wheel (SRW) use and one for dual rear wheel (DRW) configurations.

Why Load Index Matters

🏋️ Exceeding a tire's load rating — even occasionally — puts stress on the internal structure that the tire wasn't designed to handle. Over time, or in a single overload event, this can cause:

• Sidewall bulging or cracking
• Blowouts, especially at highway speeds
• Reduced steering response and longer stopping distances
• Accelerated and uneven tread wear

Your vehicle's minimum load index requirement is listed in the owner's manual and on the tire placard inside the driver's door jamb. That number is the floor — you should never install tires with a lower load index than what's specified.

Can You Go Higher Than the Recommended Load Index?

Generally, yes — installing tires with a higher load index than required is acceptable in most cases. A higher-rated tire won't hurt anything and may offer additional durability for drivers who regularly carry heavy loads or passengers.

The caveat: higher load index tires are often heavier and stiffer, which can slightly affect ride comfort and fuel efficiency. Whether that tradeoff is worthwhile depends on how you use your vehicle.

Load Range vs. Load Index: Not the Same Thing

Light truck tires sometimes use a load range designation (letters like C, D, E) instead of or alongside a load index. These correspond to ply ratings and inflation thresholds:

An LT tire's load range affects how much air pressure it can hold, which in turn determines its load-carrying capacity. A higher load range isn't always better for everyday passenger use — stiffer sidewalls can make for a rougher, less forgiving ride on lighter vehicles.

Factors That Shape What Load Index You Actually Need

The right load index for one driver is not necessarily right for another. Key variables include:

• Vehicle type — A compact crossover and a three-quarter-ton pickup have completely different load requirements
• GVWR (Gross Vehicle Weight Rating) — The manufacturer's specified maximum loaded weight determines minimum tire load capacity
• Payload and towing habits — Drivers who regularly haul tools, materials, trailers, or heavy passenger loads need to account for maximum use, not average use
• Replacement tire brand and model — Different brands may rate the same physical tire size at slightly different load capacities depending on construction
• OEM vs. aftermarket wheels — Wheel changes can affect fitment and, in some cases, recommended tire specs

The Number That Gets Overlooked Most

Most drivers focus on tire width, brand, or price. The load index gets skipped. But for trucks, SUVs used for towing, and vehicles carrying heavy equipment or large families on a regular basis, it's one of the most functionally important specs on the sidewall.

Your owner's manual and door jamb placard carry the minimum load index your vehicle requires. Whether your driving patterns, cargo habits, and vehicle configuration mean you should be at that minimum — or well above it — depends on details that only you and the vehicle in front of you can answer.