How Tall Is A 315 70 17 Tire? | Actual Inches That Matter

A 315/70R17 tire stands about 34.4 inches tall, measures 12.4 inches wide, and sits just under the mark many drivers call a 35-inch tire.

If you want the plain answer, a 315/70R17 tire is about 34.36 inches tall when you run the size math from the sidewall code. That number comes from the tire’s width, its 70-series sidewall, and the 17-inch wheel it wraps around.

That puts this size in the big-tire camp. It looks chunky, fills a wheel well nicely, and often changes how a truck or SUV sits, steers, and clears fenders. It also explains why some people call a 315/70R17 a “metric 35,” even though it usually lands a touch shorter than many true 35×12.50R17 tires.

How Tall Is A 315 70 17 Tire? The Real Math

The code 315/70R17 tells you three things right away. The tire is 315 millimeters wide, the sidewall height is 70% of that width, and the wheel diameter is 17 inches.

What Each Number Means

• 315: section width in millimeters
• 70: sidewall height as a share of the width
• 17: wheel diameter in inches

Start with the width. A 315 mm tire is about 12.40 inches wide. Then take 70% of 315 mm to get the sidewall height. That gives you 220.5 mm, or about 8.68 inches per sidewall.

Since a tire has a sidewall above the wheel and another below it, you double that sidewall number. Add the 17-inch wheel, and you land at 34.36 inches overall. That is the unloaded, nominal height. Tire Rack’s tire dimension formula uses that same method and also notes that mounted size can shift a bit by brand and measuring rim.

The Size In Inches

Here’s the clean inch conversion people usually want when they ask how tall a 315/70R17 tire is. The headline number is 34.36 inches tall, but the width and sidewall tell the rest of the story.

A sidewall a touch under 8.7 inches is a lot of rubber. That is why this size has the tall, planted look many truck owners want. It also explains why it can rub on stock suspension, stock offset wheels, or full steering lock even when the raw diameter does not look wild on paper.

Measurement	Value	What It Tells You
Section width	315 mm	Nominal width from sidewall to sidewall
Section width in inches	12.40 in	Shows how wide the tire is in shop-talk terms
Aspect ratio	70	The sidewall height is 70% of the width
One sidewall height	220.5 mm	Height from wheel to tread on one side
One sidewall height in inches	8.68 in	Shows why this size looks tall and meaty
Wheel diameter	17 in	Wheel size the tire is built to fit
Overall diameter	34.36 in	The full tire height from ground to top
Radius	17.18 in	Half the full height
Circumference	107.95 in	Distance covered in one tire turn
Revolutions per mile	About 587	Shows gearing and speedometer effect

Why This Tire Height Matters On The Truck

A 34.36-inch tire does more than change the stance. It can nudge speedometer readings, soften some of your effective gearing, and change the amount of room left near the fender liner, mud flap, sway bar, and body mount.

That extra height also lifts the axle centerline by half the diameter gain over your old tire. If you move from a tire that is 32.7 inches tall to this one, the axle only rises by about 0.83 inch, not the full 1.66-inch diameter gap. That small detail clears up a lot of confusion.

What Drivers Usually Notice After The Swap

• A fuller wheel-well look
• A wider footprint and more sidewall bulge
• Slower speedometer reading than actual road speed
• A softer launch feel with stock gearing
• More chance of rubbing at full lock or full compression

Fitment is where many builds hit a snag. Two tires stamped 315/70R17 may not stand the same once mounted and aired up. Tread depth, casing shape, wheel width, and wheel offset all move the final numbers. That is why checking the brand spec sheet and your door-jamb placard still matters. NHTSA tire placard advice points drivers back to the vehicle label and owner’s manual for the size and pressure the vehicle maker approved.

315 70 17 Tire Height Vs Common Alternatives

Most people asking about this size are comparing it with a stock truck tire or with a true flotation size. That side-by-side view makes the height easier to picture.

A 315/70R17 usually lands close to a 35-inch tire in day-to-day talk, yet it is not always the same thing. Some true 35×12.50R17 tires measure a bit over 34.5 inches, while others sit close to 34.8 or 35 inches depending on brand, tread, and measuring method.

Tire Size	Typical Height	What Changes
285/70R17	32.7 in	Easier fit, less rubbing, shorter sidewall
315/70R17	34.36 in	Big step up in height and width
35×12.50R17	34.5–35.0 in	Often a touch taller, width is similar on paper
37×12.50R17	36.5–37.0 in	Needs much more room, gearing, and brake thought

Will A 315 70 17 Tire Fit Without Mods?

Sometimes yes. Many times, not on a fully stock truck. This size is tall and wide enough that fitment depends on the exact vehicle, wheel offset, suspension height, and how much steering travel the truck has.

On some half-ton trucks, a mild level or small lift is enough. On others, rubbing starts at the front liner or body mount even before the suspension cycles hard. A wheel with the wrong offset can make the tire poke out and catch the fender edge, or tuck in and kiss the upper control arm.

Check These Spots Before You Buy

• Front fender liner at full lock
• Body mount or pinch weld area
• Mud flap and lower valance
• Upper control arm clearance
• Wheel width and offset
• Spare tire space if you want a full-size spare

There is another wrinkle. “How tall” on paper and “how tall” on your truck are not always twins. Brand A may list a 315/70R17 at 34.4 inches on its measuring wheel. Brand B may list the same stamped size at 34.8. Mud-terrain tread blocks can also stand taller when new, then lose a bit of height as they wear in.

What A 315 70 17 Tire Means For Speedometer And Gearing

If your old tire was shorter, your speedometer will usually read low after the jump to a 315/70R17. Say the truck came with a 285/70R17 at about 32.7 inches tall. The new tire is about 5.1% taller. When the speedometer shows 60 mph, your real speed is close to 63 mph.

You may also feel the truck hold gears a bit longer or pull a touch softer off the line. That is normal. A taller tire travels farther per revolution, so the drivetrain acts like it has a taller final drive ratio. Trucks with strong factory gearing shrug this off better than trucks that were lazy to start with.

If you tow, haul, or wheel in slow terrain, that change may matter more than the raw height figure. In that case, the tire is not just “34.4 inches tall.” It is also a gearing change, a clearance change, and a weight change rolled into one.

The Number Most Buyers Need

A 315/70R17 tire is about 34.36 inches tall, about 12.40 inches wide, and close enough to a 35 that many drivers group it in that camp. The catch is fitment. The stamped size gives you the math, but the final mounted height can shift a bit by tire model and wheel setup.

If you are choosing this size for your truck, use the 34.4-inch figure as your baseline, then check brand specs, wheel specs, and the space your truck actually has at full lock and full compression. That keeps the choice grounded in numbers, not guesswork.