What tire is close to a 33?

[SanIan]

The most direct metric equivalent to a “33-inch” tire is the 285/70R17, measuring approximately 32.8 inches in diameter. Other common sizes like the 285/75R16 and 275/60R20 also achieve a near-33-inch height. These metric tires provide similar ground clearance but are typically narrower (around 11.2-11.5 inches wide) than traditional 33x12.50R15LT flotation tires.

For a clear comparison, here are the primary metric sizes considered 33-inch equivalents:

Metric Tire Size	Approx. Diameter	Approx. Width	Common Vehicle Fitment
285/70R17	32.8 inches	11.2 inches	Half-ton trucks, SUVs (e.g., Ford F-150, Toyota Tundra)
285/75R16	32.8 inches	11.2 inches	Older 3/4-ton trucks, SUVs with 16-inch wheels
275/60R20	33.0 inches	10.8 inches	Modern trucks/SUVs with factory 20-inch wheels
305/70R16	33.0 inches	12.2 inches	Wider option for 16-inch wheels, may require lift
305/55R20	33.2 inches	12.0 inches	Common alternative for 20-inch wheels, offers wider stance

The 285/70R17 stands out as the most popular choice for daily-driven trucks. Its balanced dimensions often allow it to fit with minimal or no trimming, especially on vehicles with a leveling kit or a 2-inch lift. The narrower width compared to a 12.50-inch tire results in less impact on fuel economy and acceleration, while still offering substantial off-road clearance.

It’s crucial to understand the width variance. While called “33s,” many 285-width tires are slightly under 33 inches. Industry data from major tire manufacturers like BFGoodrich and Toyo consistently list the 285/70R17 KO2 or Open Country at 32.8 inches. This small difference results in a speedometer error of roughly 3-5%, meaning your displayed speed will read slightly slower than your actual speed.

When choosing between a 285 and a classic 33x12.50, the key trade-off is width. The metric tire is about an inch narrower. This can be beneficial for winter driving, as narrower tires often cut through snow better. However, for maximum off-road traction and appearance, the wider flotation tire is preferred but usually requires correct wheel backspacing to avoid rubbing on suspension components.

[DiAriel]

I just went through this for my 2019 Silverado. Everyone online says “get 33s,” but that’s not a tire size you can just pick off the shelf. My mechanic pointed me to the 285/70R17. It’s the go-to. Slipped right on with a 2-inch leveling kit, no cutting needed. The truck looks taller, fills the wheel well perfectly, and the ride is still smooth. My speedo is off by about 4 mph at 70, which is normal. For a simple, bolt-on upgrade that gives you the “33-inch” look, this is the one.

[LaEmerson]

As an off-road shop manager, I explain this daily. “33-inch” is a target diameter. The metric system gets you there differently. Think of the first number (e.g., 285) as the tire’s width in millimeters. The second number (70) is the aspect ratio—the sidewall height as a percentage of the width.

So, a 285/70R17 has a sidewall that is 70% of 285mm tall. Do the math, convert to inches, add the wheel diameter, and you get ~32.8”. That’s your 33. The 285/75R16 is a different recipe but yields a similar final height. The advantage of the metric route is precision and a massive variety of all-terrain and highway tire models you won’t find in the old flotation size.

[TaylorLee]

If your truck came with 20-inch wheels, your path to 33s is different. You can’t fit much sidewall, so you use a wider, lower-profile tire. The 275/60R20 is a nearly exact 33-inch diameter. The 305/55R20 is another favorite—it’s slightly taller and noticeably wider, giving a more aggressive stance. The 20-inch wheel crowd often picks the 305/55R20 because it maintains the factory wheel’s look but transforms the vehicle’s presence. Just check your front wheel well clearance at full lock; sometimes a minor trim is needed on the inner liner.

[Edgar]

Let’s talk about the trade-offs you’re actually making. Yes, a 285/70R17 is the closest match to a 33-inch diameter. But “close” means your actual diameter is about 32.8 inches. This creates a 3% speedometer error. If your speedo reads 70 mph, you’re actually doing about 72. That’s important for your odometer and trip calculations over time.

The other big point is width. A true 33x12.50R15 is over 12 inches wide. A 285mm tire is about 11.2 inches. That narrower width is better for daily driving—less road noise, better wet weather handling, and less strain on your powertrain. But on loose sand or mud, the wider tire will provide a larger contact patch. Your choice depends on whether you prioritize on-road manners or ultimate off-road footprint. For 80% of truck owners using it as a daily driver with occasional trails, the 285 metric is the smarter, more functional choice.