245/75r16 vs 285/75r16 Tire: What’s the Difference?

You might choose new tires for your car for various reasons, including changing old or damaged tires or simply changing the overall appearance of your vehicle. In this process, you might have thought about whether 245/75r16 and 285/75r16 tires are interchangeable.

If this describes you, then this post is meant just for you. Today in this guide, we will try to find out the answer to whether these tires are interchangeable or not. We will break down a complete comparison between 245/75r16 vs 285/75r16 tires.

When it comes to replacing your automobile tires, there are several crucial considerations to make. So be sure to keep reading to learn more.

245/75r16 vs 285/75r16 Tire: Comparison Table

In our comparison table below, we will see all the differences between 245/75r16 and 285/75r16 tires.

245/75r16 TireType285/75r16 Tire
31.47  inches or 799.3 mmDiameter difference 2.36 (60) 7.5% inches (mm)33.83 inches or 859.3 mm
9.65 inches 245 mmWidth difference 1.57 (40) 16.3% inches (mm)11.22 inches 285 mm
98.86 inches or 2511.08 mmCircumference difference 7.42 (188.5) 7.5% inches (mm)106.28 Inches or 2699.57 mm
7.23 inches or 183.75 mmSidewall Height difference 1.18 (30) 16.3% inches (mm)8.42 inches or 213.75 mm
640.9 RPM or 398.24 KMRevolutions per mile difference -44.75 (-27.81) -7%  (km)596.15 RPM or 370.43 KM

These tires have a small difference in diameter, as we can see from the chart above. A 245/75r16 tire has a diameter of 31.47 inches, while a 285/75r16 tire has a diameter of 33.83 inches. As a result, the diameter difference is 7.5 percent, which is rather significant.

The 285 tire series, on the other hand, is wider than the 245 tire series. Whenever it comes to deciding which tire size to use on which vehicle, the variation is not insignificant. Similar to the diameter, there is a huge 16.3% variation between both tires.

Another factor we need to discuss is the sidewall height change between the 245/75r17 and 285/75r17 tires is 16.3%. So, there will be issues with high traction and suspension.

How to read the tire sizes 245/75r16 and 285/75r16?

There are four parts to the tire size 245/75r16, and each part bears a certain meaning. Before you decide to interchange or replace the Tire, you must learn about them. Here is the explanation of each part of the tire size 245/75r16.

  • 245 means the width of the tires in millimeters
  • 75 shows the percentage of height to the width or the Aspect Ratio
  • R indicates Radial Construction
  • 16 indicates the Diameter of the Rim

Doing the Same for Tire Sizes 285/75r16.

  • 285 means the width of the tires in millimeters
  • 75 shows the percentage of height to the width or the Aspect Ratio
  • R indicates Radial Construction
  • 16 indicates the Diameter of the Rim

What’s The Difference Between 245/75r16 and 285/75r16 Tire?

By now you’ve learned the basics of using two tires interchangeably, now let’s see implementing the theory in a real example. Below, we have compared 245/75r16 and 285/75r16 tires in terms of width, aspect ratio, construction materials, and rim diameter.

Width

If you measure from one sidewall to the other sidewall of a tire, you will get the width. It is expressed in millimeters. You can instantly learn the Width of a tire just by looking at the tire size index.

The first three digits of a tire size index indicate the Width of that tire. As you can see, the first three digits of 245/75r16 are 245. It means the width of that tire is 245 millimeters. 

Likewise, the three-digit number of 285/75r16 is 285. It means the Width of that tire is 285 millimeters. So the difference in the Width is 285 – 245 = 40 millimeters.

Now, if you switch to the tire size which is 0 millimeters more or less in Width, it shouldn’t be a problem. 

But you cannot switch tire size depending on Width only. You must consider the Sidewall Height as well. The Sidewall Height depends on Width and Aspect Ratio.

Aspect Ratio

As you can see, there is no difference between the Aspect Ratio of the two tire sizes. Both tires have an Aspect Ratio of 75%. 

But it doesn’t mean that the sidewall height of the two tires will be similar. Due to the difference in Width, the sidewall heights will be dissimilar.

Let’s start with the simple question first: what is the Aspect Ratio? And its relation with other measurements.

Aspect Ratio is the ratio of the sidewall from wheel to tread and the width. This measurement is usually represented in a percentage. 

In our example, 245/75r16 Tire size has a width of 245 with an aspect ratio of 75%. So the sidewall height will be 245 x 0.75 or 7.2 inches or 183.75 mm. You can get the number by simply putting the value on the equation.

Equation: Height of a Sidewall = Aspect Ratio of Tire x Width.

On the other hand, the Sidewall Height of 285/75r16 is 8.4 inches.

As you can see, there’s a huge difference between the sidewall heights of the two tires.

Though there are no differences in the Aspect Ratio, the two tire sizes are not interchangeable due to the gaps in Width and Sidewall Height.

Construction Type

The tire size index informs you about the Construction Type of a tire. It is expressed by a letter in the tire size index. 

Both 245/75r16 and 285/75r16 have the same letter ‘R’. So, both the tires have Radial Construction in terms of construction type.

Such tires have a sophisticated construction with square footprints on the top. The Radial tires are ideal for driving on-road. 

They are resistant to heat and water. They are next-gen tires and can provide great fuel efficiency.  

Another famous construction type is Bias Ply. They are also known as Cross-ply. It is expressed by the letter ‘B’ in a tire size index. This type is great for driving off-road.

Rim Diameter

To know which tire size fits your vehicle, you must know the wheel rim size of your vehicle as well as the Rim Diameter of a tire. 

For instance, if your vehicle has a 16-inch wheel rim, you can use the tire which has a 16-inch Rim Diameter.

By looking at a tire size index, you can learn instantly the Rim Diameter of a tire. The last two digits of a tire size index indicate the Rim Diameter. It is measured in inches. 

As you can see, the Rim Diameter of 245/75r16 is 16 inches. Similarly, the Rim Diameter of 285/75r16 is 16 inches.

If your vehicle has a 16-inch wheel rim, you can use both tire sizes. But make sure to use the same size tires for all the wheels.

Can You Interchange Between 245/75r16 vs 285/75r16 tires?

No, you cannot interchange between 245/75r16 and 285/75r16 tires, and the main reason for that is the huge diameter difference of 7.5% between these tires. Even if you interchange your tires, the speed of your car will be reduced during acceleration as the wheel is heavier. 

Moreover, the sidewall length is also very high, which means it can cause harm to the shock absorber and possibly the wheels of your car and the possibility of an erroneous speedometer reading.

Speedometer Difference: Using the current Tire Size 245/75r16 Instead Of the New Tire Size 285/75r16

Look at the Table. It shows differences in speedometer reading and the actual speed at any given time when the current Tire Size is 245/75r16 instead of 285/75r16. 

Speedo ReadingActual Speed
20 mph (32.19 km/h)21.5 mph (34.6 km/h)
25 mph (40.23 km/h)26.88 mph (43.25 km/h)
30 mph (48.28 km/h)32.25 mph (51.9 km/h)
35 mph (56.33 km/h)37.63 mph (60.56 km/h)
40 mph (64.37 km/h)43 mph (69.21 km/h)
45 mph (72.42 km/h)48.38 mph (77.86 km/h)

Speedometer Difference: Using current Tire Size 285/75r16 Instead Of New Tire Size 245/75r16

The table shows the differences in speedometer reading and the actual speed at any given time when the current Tire Size is 285/75r16 instead of 245/75r16.

Speedo ReadingActual Speed
20 mph (32.19 km/h)18.6 mph (29.94 km/h)
25 mph (40.23 km/h)23.25 mph (37.42 km/h)
30 mph (48.28 km/h)27.91 mph (44.91 km/h)
35 mph (56.33 km/h)32.56 mph (52.39 km/h)
40 mph (64.37 km/h)37.21 mph (59.88 km/h)
45 mph (72.42 km/h)41.86 mph (67.36 km/h)

What you must consider Before Interchange or Replace Tire? 

There are important things to consider Before replacing or swiping the Tires. You cannot simply replace the 245/75r16 tire with the 285/75r16 tire that is in a different shape.

For example, if the aspect ratio of the existing tire is 40%, replacing it with a tire that has an aspect ratio of  45% might not be a good option.

Doing so will have various consequences on the car’s overall performance, such as variations in top speed and speedometer.

However, to a certain extent, such as minor changes in the diameter or the sidewall, you can switch Tires. However, this can only be done in compliance with the manufacturers’ recommendations.

Anyway, when replacing the Tire, the simple guideline to follow is that the current tire’s size, load index, and speed rating should all match with the replacement Tire.

Load Index and Speed Index of a Tire 245/75r16 and 285/75r16

The load index refers to the maximum load-bearing capacity, whereas the speed index refers to the Tire’s maximum allowable speed at a full load. These are very crucial stats to know before you decide to interchange tires.

Index information can be found on the sidewall right after the Tire size number. It is a combination of numbers and letters that bear a particular meaning. 

Here is an example of how the index information is usually written on the sidewall: 245/75r16 90A. The 90A stands for load and speed index, with 90 indicating a maximum load-bearing capacity of 600 kg, whereas ‘A’ denotes an allowed speed of up to 170 km/h.

Check the load and speed index. They must be as close as possible to fit precisely. These values change depending on the vehicle’s weight and wheel size. Here is a table that shows various load and speed indexes, so you get the idea.

Load IndexKgSpeed IndexSpeed Limit
65290QUp to 160 Km/h
66300RUp to 170 Km/h
67307SUp to 180 Km/h
68315TUp to 190 Km/h
69325HUp to 210 Km/h

Size of the Tire 

The size of the Tire is another vital piece of information to know to exchange the tires properly. The large number on the sidewall shows the tire size.

For example, the marking 245/75r16 on the sidewall represents the size of the Tire. You can also find it in the user manual, on the sidewall, and in other places such as inside the fuel flap or glove compartment.

What Size Tires Is 245/75r16 in Inches?

245/75r17 tires have a 31.5″ diameter, 9.6″ section width, and 16″ wheel diameter.

The circumference is 98.8″ and they make 641 revolutions per mile. The Sidewall Height of this Tire is 7.2 inches.

What Size Tires Is 285/75r16 in Inches?

285/75r17 tires have a diameter of 33.8″, a section width of 11.2″, and a wheel diameter of 16″.

The circumference is 106.2″  and they have 596 revolutions per mile. The Sidewall Height of this Tire is 8.4 inches.

Conclusion

Your tires are responsible for everything from the car’s control and efficiency. As a result, obtaining the right tire size for your automobile is critical for your safety and pleasant riding experience.

As a result of reading our guide, we trust by now; you are aware of the differences between 245/75r16 and 285/75r16 tires, as well as if they are interchangeable or not.

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