Tire Size 245/75r17 vs 235/80r17

The main difference between 245/75r17 and 235/80r17 tires is the width. The 245/75r17 is 10mm wider than the 235/80R17. This means that the 245/75r17 will have a slightly larger contact patch with the road, which can improve handling and grip. However, the 245/75r17 will also have a slightly higher rolling resistance, which can reduce fuel economy.

245/75r17 vs 235/80r17 Table

To better understand the differences between 245/75r17 and 235/80r17 tire sizes, refer to this informative comparison table.

Diameter inches31.47 (799.3)31.8 (807.8)0.33 (8.5)
Width inches9.65 (245)9.25 (235)-0.39 (-10)
Circum. inches98.86 (2511.08)99.91 (2537.78)1.05 (26.7)
Sidewall Height7.23 (183.75)7.4 (188)0.17 (4.25)
Revolutions640.9 (398.24)634.15 (394.04)-6.74 (-4.19)

Two Main Differences

  • The 235/80R17 tire has a slightly larger overall diameter (31.8 inches) compared to the 245/75R17 tire (31.47 inches). This 1.1% difference can impact the vehicle’s speedometer reading, ground clearance, and stability.
  • The 245/75R17 tire is wider, with a section width of 9.65 inches, compared to the 235/80R17’s 9.25 inches. This 4.1% decrease in width can influence the vehicle’s handling and traction.

Overall Diameter
The overall diameter of a tire is the total height from the base of the tire’s tread to the top. The 235/80R17 has a larger diameter (31.8 inches) compared to the 245/75R17 (31.47 inches), a difference of 0.33 inches or 8.5mm.

A larger diameter tire may improve the vehicle’s ground clearance, making it a good choice for off-road conditions. However, it may also result in slightly slower acceleration and slight variation in the speedometer reading.

Section Width
Section width, or tire width, is the measurement of the tire’s width from its inner sidewall to the outer sidewall. The 245/75R17 has a wider section (9.65 inches) compared to the 235/80R17 (9.25 inches), a difference of 0.39 inches or 10mm.

A wider tire generally offers better traction and stability, especially in wet conditions. On the flip side, it might also lead to increased rolling resistance and, consequently, slightly reduced fuel efficiency.

Circumference is the distance around the outer edge of the tire. The 235/80R17 tire has a slightly larger circumference (99.91 inches) compared to the 245/75R17 tire (98.86 inches).

The difference of 1.05 inches or 26.7mm, although marginal, may impact the tire’s revolutions per mile and the vehicle’s overall handling.

Sidewall Height
Sidewall height is the distance from the rim to the tread. The 235/80R17 tire has a larger sidewall height (7.4 inches) than the 245/75R17 tire (7.23 inches), a difference of 0.17 inches or 4.25mm.

A larger sidewall can contribute to a smoother ride by absorbing more shock from road imperfections but may decrease precision in handling, particularly when cornering at higher speeds.

Revolutions Per Mile
Revolutions per mile refer to how many times a tire will rotate in one mile. The 235/80R17 has fewer revolutions per mile (634.15) compared to the 245/75R17 (640.9), a difference of 6.74 revolutions.

Fewer revolutions per mile could result in slightly better fuel efficiency due to less rolling resistance, but it could also mean slightly less accurate speedometer readings.

Wheel Size
Both tires are meant for 17-inch wheels and have a radial construction type (indicated by the ‘R’ in their sizes). This construction is designed to provide a smooth and comfortable ride with improved handling, making them suitable for various vehicles and driving conditions.

Alternative Tire Size of 235/80r17
The overall diameter of the replacement tires must not deviate by more than 3% from that of the original tires.

Tire SizeOverall DiameterDifference
235/75R1730.9″ (784 mm)-3%
255/70R1731.1″ (790 mm)-2.2%
275/65R1731.1″ (790 mm)-2.2%
305/60R1731.4″ (798 mm)-1.2%
245/75R1731.5″ (800 mm)-1%
285/65R1731.6″ (802 mm)-0.7%
265/70R1731.7″ (804 mm)-0.5%
345/55R1732″ (812 mm)0.5%
255/75R1732″ (814 mm)0.7%
275/70R1732.2″ (818 mm)1.2%
305/65R1732.6″ (828 mm)2.5%
285/70R1732.8″ (832 mm)3%
235/85R1732.8″ (832 mm)3%

Alternative Tire Size of 245/75r17
It is required that the replacement tires have an overall diameter within 3% of the original tires.

Tire SizeOverall DiameterDifference
235/75R1730.9″ (784 mm)-2%
275/65R1731.1″ (790 mm)-1.3%
255/70R1731.1″ (790 mm)-1.3%
305/60R1731.4″ (798 mm)-0.2%
285/65R1731.6″ (802 mm)0.2%
265/70R1731.7″ (804 mm)0.5%
235/80R1731.8″ (808 mm)1%
345/55R1732″ (812 mm)1.5%
255/75R1732″ (814 mm)1.8%
275/70R1732.2″ (818 mm)2.3%

Our Observation
While the differences between the 245/75R17 and the 235/80R17 are subtle, they can have distinct impacts on vehicle performance. The 235/80R17, with its larger diameter and sidewall height, is better suited for off-roading and comfort-oriented vehicles.

In contrast, the 245/75R17, with its wider section width, offers better traction and stability, making it suitable for vehicles driven in challenging weather conditions or requiring more precise handling.

However, these are general observations, and the actual impact will depend on the specific vehicle, driving conditions, and driver preferences. As always, it’s advisable to consult with a tire expert or your vehicle manufacturer when choosing the right tire size for your vehicle.

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