Tire load range is a letter code that tells you the maximum weight a tire can safely carry at its rated pressure

Every tire sold in the United States carries a load range printed on its sidewall — a single letter from A through F. That letter is not arbitrary. It represents the maximum load each tire can support when inflated to its rated pressure, and it must match your vehicle's weight and the load your tires will actually carry. Using a tire with too low a load range risks blowouts and loss of control. Using one rated higher than necessary costs more money for capacity you do not need.

Load range replaced an older system called "ply rating" in the 1960s, though many people still use the terms interchangeably. The letter does not tell you how many layers of material are inside the tire — it tells you the structural strength of the tire as a whole, which determines how much weight it can bear.

Key Takeaways

  • Load range letters run from A (lightest) through F (heaviest), and your vehicle's owner manual specifies which range your tires must fall within.
  • The load index number on your tire's sidewall (usually between 70 and 130) is the numerical equivalent of load range and appears on your tire size label.
  • Passenger cars typically use load range C or D; light trucks and SUVs often use E or F, which have reinforced sidewalls to handle heavier loads.
  • Mismatched load ranges across your four tires can cause uneven wear and handling problems, so all four should be the same range unless your manual permits otherwise.
  • Load range is separate from speed rating and tread wear rating — you need to check all three when replacing tires to may support they meet your vehicle's requirements.

How load range letters correspond to weight capacity

Load range A is the lightest and is rarely seen on new vehicles sold today — it was common on older compact cars and some economy sedans. Load range B is also uncommon in the current market. Load range C is standard on most passenger sedans and smaller crossovers. Load range D appears on larger sedans, some SUVs, and minivans. Load range E is typical for pickup trucks, full-size SUVs, and vehicles designed to tow or carry heavy cargo. Load range F is the heaviest and is used on heavy-duty trucks and commercial vehicles.

The actual weight capacity depends on the tire size and pressure rating as well as the load range letter. A tire marked "225/65R17 102H" carries a load index of 102, which corresponds to a specific weight in pounds — in this case, 2,039 pounds per tire. That number is always listed on the tire's sidewall near the load range letter. Your vehicle's door jamb or owner manual will specify the load index your tires must meet, and you must not go below it.

Load range and load index are two ways of saying the same thing. Load range uses letters; load index uses numbers. A tire with load range D might have a load index of 104, while a load range E tire of the same size might be 110. When shopping for replacement tires, you will see both numbers on the sidewall and in the tire specification sheet.

Why your vehicle specifies a minimum load range

Your vehicle's weight, plus the weight of passengers and cargo it is designed to carry, determines the minimum load range required. Manufacturers test tires under load and measure how they perform — how much heat they generate, how the sidewalls flex, how the tread wears. A tire rated for a lower load than your vehicle needs will flex too much, generate excessive heat, and fail prematurely or suddenly.

The load range also affects the tire's internal structure. A load range E tire has reinforced sidewalls and a stiffer carcass than a load range C tire of the same size. That reinforcement allows it to carry more weight, but it also changes how the tire rides and handles. A load range E tire on a car designed for load range C will feel stiffer and may ride harshly because it is over-engineered for that vehicle's actual needs.

Conversely, using a load range lower than specified is dangerous. If you install load range C tires on a truck that requires load range E, the tires will overheat and fail, especially if you are carrying cargo or towing. The sidewalls will flex excessively, the tire will lose pressure, and you risk a blowout at highway speed.

Where to find your vehicle's load range requirement

Your vehicle's required load range is printed on a label inside the driver's door jamb, on the fuel door, or in the owner's manual. The label lists the tire size (for example, 225/65R17) and the load index number (for example, 102). Some labels also show the load range letter directly. If your label shows only the tire size and load index, you can cross-reference that load index to find the corresponding load range letter on any tire's sidewall.

Do not assume that all tires of the same size have the same load range. A 225/65R17 tire can be load range C, D, or E depending on the tire model and manufacturer. You must match the load index number specified on your vehicle's label, not just the tire size. If your label says load index 102, you must buy a tire with load index 102 or higher — you cannot go lower.

Load range versus speed rating and tread wear

Load range is one of three ratings you must check when buying replacement tires. Speed rating (a letter like H, V, or W) tells you the maximum speed the tire can sustain safely. Tread wear rating (a number like 500 or 800) is a measure of durability and how long the tread is expected to last under standard conditions. All three must meet or exceed your vehicle's requirements.

A tire marked "225/65R17 102H 500" has a load index of 102, a speed rating of H (130 mph), and a tread wear rating of 500. Your vehicle's door jamb label will specify the minimum for each. If your label says "102 H," you need at least load index 102 and speed rating H. The tread wear rating is your choice — a higher number means longer-lasting tread, but it is not a safety requirement.

What happens if all four tires have different load ranges

Mixing load ranges across your four tires is not recommended and can cause handling problems. If three tires are load range D and one is load range C, the load range C tire will flex more under load, wear faster, and may fail before the others. This uneven behavior can make the vehicle pull to one side or feel unstable in turns, especially when fully loaded or towing.

Some vehicles with different front and rear axle weights may have different load ranges front and rear — your owner's manual will specify this if it applies. In that case, you must use the correct load range for each axle. But all four tires should never be a random mix. When you replace tires, replace all four at the same time if possible, or at least replace them in pairs (both fronts or both rears) with the same load range.

Load range for trailers and specialty vehicles

Trailers have their own load range requirements based on the trailer's weight and axle configuration. A utility trailer or boat trailer will have a tire size and load index printed on the sidewall of its tires, and you must match that specification exactly when replacing trailer tires. Using a lower load range on a trailer is especially dangerous because trailers often sit stationary for long periods, and underrated tires can fail suddenly when the trailer is put back into use.

RVs, motorhomes, and commercial vehicles follow the same principle — the manufacturer specifies the load range required, and you must not go below it. Some heavy-duty vehicles may require load range F or even specialized commercial tire ratings. Always check your vehicle's documentation before buying replacement tires, regardless of vehicle type.

Frequently Asked Questions

Can I use a higher load range than my vehicle requires?

Yes, you can use a higher load range than specified, but there is no safety benefit and it costs more. A load range E tire on a car that requires load range C will work, but it will ride stiffer and wear differently than the original tires. Stick to the load range your vehicle's label specifies unless you have a specific reason to carry heavier loads than the vehicle was designed for.

What is the difference between load range and ply rating?

Ply rating is an older system that counted the number of fabric layers in the tire. Load range replaced it because the number of plies does not directly determine load capacity — tire construction and materials matter more. A modern load range E tire may have fewer plies than an old ply-rated tire, but it carries more weight. The two terms are not interchangeable, though some people still use "ply rating" informally.

If my tire sidewall shows both a letter and a number, which one do I use?

Both refer to the same thing. The letter is the load range (A through F), and the number is the load index (70 to 130 or higher). Your vehicle's label specifies the load index number, so use that to match your tires. The load range letter will appear on the tire's sidewall near the load index, and they will always correspond to each other.

Do all-season tires have different load ranges than summer or winter tires?

Not necessarily. All-season, summer, and winter tires of the same size can all come in the same load range, or they can differ. The load range depends on the specific tire model and manufacturer, not the season rating. When replacing tires with a different type (switching from all-season to winter, for example), check the load index of the new tire against your vehicle's requirement — do not assume it is the same.