What Does 108H Mean On A Tire? | Load Speed Decoded

108H marks a tire’s load index and speed rating: 108 means up to 2,205 pounds per tire, and H means up to 130 mph.

If you spot 108H on your tire sidewall, you’re looking at a two-part code that tells you how much weight that tire can carry and the top speed class it was built for. That matters when you’re replacing tires, checking fitment, or trying to figure out whether a used set matches your vehicle.

The number and letter are not random. “108” is the load index. “H” is the speed symbol. Put together, they form part of the tire’s service description. That service description works alongside the tire size, inflation pressure, and the vehicle placard on the driver’s door jamb.

Most drivers don’t need to memorize the whole sidewall. You just need to know what each part does, why it matters, and when a different rating is fine or a bad idea. Once you know that, 108H stops looking like tire jargon and starts reading like plain information.

What Does 108H Mean On A Tire? Breaking Down The Code

What 108 Means

The “108” part is the tire’s load index. Load index is a standardized number tied to a chart. It does not show pounds or kilograms by itself. You look up the number, then match it to the actual carrying limit.

Per-Tire Capacity

For a passenger tire, load index 108 equals 2,205 pounds, or 1,000 kilograms, for one tire when it’s inflated correctly. That means a full set of four 108-rated tires has a combined raw carrying figure of 8,820 pounds. Still, that does not mean your vehicle can carry 8,820 pounds. Your actual limit is still capped by the vehicle maker’s axle ratings, suspension, wheels, and door-jamb placard.

What H Means

The “H” part is the speed rating. In this case, H means the tire falls into a class rated up to 130 mph, or 210 km/h, under controlled test conditions.

Not A Daily Driving Target

That letter is not a suggestion to drive that fast. It’s a design rating tied to heat resistance, durability, and stability at speed. A tire with a higher speed symbol is often built with a different construction and compound than a lower-rated tire in the same size.

Why The Number And Letter Sit Together

Load index and speed symbol work as a pair. A tire can be the right size and still be the wrong fit if its service description is too low. Say your original tire is 225/60R18 108H. Swapping to another 225/60R18 tire with a lower load index or lower speed symbol can leave you with a tire that no longer matches the vehicle’s requirements.

That’s why tire shops ask for your full sidewall code, not just width and diameter. The size gets the tire onto the wheel. The service description helps keep the tire matched to the car’s weight and speed class.

Why 108H Matters When You’re Buying Replacement Tires

This rating matters most when you’re shopping replacements. Plenty of tires share the same size but come with different service descriptions. That happens a lot with SUVs, crossovers, minivans, and heavier sedans, where one trim may need a higher load index than another.

If your door placard or original tire calls for 108H, that is the floor you should match. Going above it is often allowed. Going below it is where trouble starts. A lower load index cuts carrying capacity. A lower speed symbol can also change the way the tire handles heat and sustained highway use.

There’s also a ride-quality angle. Two tires with the same size can feel different because of load and speed construction. A stiffer tire may feel more planted. Another may ride softer. But fit should come first. Comfort comes after the tire meets the vehicle’s rating.

Sidewall Marking	What It Means	Why It Matters
225	Tire width in millimeters	Helps determine fit on the wheel and inside the fender
60	Aspect ratio	Shows sidewall height as a percentage of width
R	Radial construction	Tells you the tire’s internal build type
18	Wheel diameter in inches	Must match the wheel exactly
108	Load index	Points to a 2,205 lb carrying limit per tire
H	Speed symbol	Shows the tire’s 130 mph speed class
XL	Extra Load	Means the tire is built to carry more load at higher pressure
M+S	Mud and snow marking	Signals all-season style tread intent, not severe-snow proof
DOT Code	Plant and production date code	Lets you check the tire’s age

108H Tire Rating In Plain English

Put in plain terms, a 108H tire is built to carry a fairly stout load and run in an H speed class. You’ll often see that sort of rating on crossovers, SUVs, light vans, and some passenger vehicles that need a stronger tire than a basic sedan tire.

That does not mean every 108H tire is the same. Tread pattern, compound, wet grip, winter traction, sidewall stiffness, and treadwear can still vary a lot from one model to another. 108H only tells you the carrying class and speed class. It does not tell you whether the tire is quiet, sporty, long-wearing, or strong in snow.

It also helps to know that passenger tires usually show one load index number. Light-truck tires can show two numbers, such as 120/116, because they may be rated one way in single use and another in dual-wheel use.

When 108H Is A Match And When It Isn’t

The cleanest move is to match what the vehicle maker calls for. The placard on the driver’s door jamb and the owner’s manual are the first places to check. Tire makers say the same thing: the load index should meet or exceed the original requirement, and the speed symbol should also meet the vehicle spec. You can see that in Goodyear’s load index chart and in Bridgestone’s speed rating page.

Using A Higher Load Index

A higher load index is often fine. A 109H or 110H tire can carry more weight than a 108H tire. But that does not raise your vehicle’s own carrying limit. It only means the tire itself has a higher carrying class.

Using A Lower Load Index

Dropping below 108 is where you need to stop and double-check. A lower number means less carrying ability. Even if the tire size matches, that lower rating can make it the wrong replacement.

Using A Higher Speed Symbol

Moving from H to V or W is common on some replacement choices, as long as the tire also fits the vehicle and wheel. Drivers sometimes notice a different ride feel because the casing and tread package may change with the higher speed class.

Using A Lower Speed Symbol

Dropping from H to T or S is not something to do casually. Even when the tire physically fits, it may no longer match the car maker’s intended spec. That can matter on hot roads, long highway runs, and heavier vehicles.

Service Description	Per-Tire Load Limit	Speed Class
106H	2,094 lb	130 mph
107H	2,149 lb	130 mph
108H	2,205 lb	130 mph
109H	2,271 lb	130 mph
108V	2,205 lb	149 mph
110H	2,337 lb	130 mph

A Simple Checklist Before You Buy

If you’re replacing a tire marked 108H, run through these checks before you hit “buy” or approve a shop order:

• Match the full tire size, not just the wheel diameter.
• Match or exceed the 108 load index.
• Match or exceed the H speed symbol unless the vehicle maker allows a seasonal exception.
• Check the driver’s door placard for the original spec and pressure.
• Check whether the original tire was marked XL.
• Make sure all four tires are the same service description when possible.
• Check the DOT date code if you’re buying a used or older new tire.

That list catches most buying mistakes. It also keeps you from paying for a tire that fits the wheel but not the vehicle.

Mistakes Drivers Make With 108H

The most common mistake is treating 108H like a minor detail. It’s easy to focus on size alone and miss the service description. That can leave you with a tire that looks right on paper but carries less load than the vehicle was set up for.

Another mistake is thinking the H means the tire should be driven at 130 mph. It does not. It’s a speed class created through standardized testing. Real-world driving adds heat, rough pavement, cargo, potholes, weather, and pressure changes. All of that changes what the tire deals with on the road.

One more slip-up is assuming the combined tire load figure is the same as payload. It isn’t. The vehicle still has its own weight limits. Tires are one part of that puzzle, not the whole answer.

So if your tire says 108H, the plain read is this: each tire is rated to carry up to 2,205 pounds, and it belongs to the H speed class. Match that rating to your placard, keep the tire inflated properly, and you’ll be reading the code the way tire shops and vehicle makers do.