Tire Size 285/70r17 vs 275/70r18
The main difference between tire sizes 285/70R17 and 275/70R18 lies in their width and diameter. The 285/70R17 is wider by 10mm and has a smaller diameter of 11.4mm compared to the 275/70R18.
| / | R |
| / | R |
| Parameter | 235/35 R18 | 205/40 R18 | Differ. |
|---|---|---|---|
| Tire Height | |||
| Section Width | |||
| Circumference | |||
| Sidewall Height | |||
| Revolutions | |||
| Rim Size |
Fitment
The 285/70r17 has a width of 11.22 inches and a diameter of 32.71 inches. The 275/70r18 is slightly narrower at 10.83 inches wide, with a diameter of 33.16 inches.
The 275/70r18 is within 3% of the 285/70r17’s overall diameter, meaning it can directly replace it without adaptation needed.
Ground Clearance
With a diameter of 33.16 inches, the 275/70R18 provides 1.08 inches more ground clearance than the 285/70R17.
This added clearance is useful for off-road driving, helping avoid scrapes over terrain. However, it causes a slightly lower speedometer reading.
Fuel Efficiency
The narrower 275/70R18 has a smaller contact patch and lower rotational mass, improving fuel efficiency compared to the wider 285/70R17. This saves on gas costs for daily driving.
Ride Comfort
The 275/70R18’s taller 70 aspect ratio sidewall cushions bumps better than the 285/70R17. Its extra flex absorbs road impacts, providing a smoother ride over uneven surfaces.
Handling
The shorter sidewall of the 285/70R17 offers quicker steering response and handling precision on pavement compared to the 275/70R18. However, both deliver responsive handling.
Noise & Vibration
The 285/70R17’s stiffer sidewall transmits more road noise and vibration into the cabin. The 275/70R18’s extra sidewall flex dampens noise and vibration better.
Durability
The narrower 275/70R18 may exhibit more even treadwear and a longer lifespan. The wider 285/70R17 is heavier, adding stress and wear on components.
Adverse Conditions
Performance in rain, snow, and off-road is very similar. The 275/70R18’s extra clearance provides a slight advantage, while the 285/70R17 is a bit more responsive. Both handle adverse conditions well.
Speedometer Difference
At a vehicle speed of 20 mph, the speedometer reading will be slightly different between 285/70r17 and 275/70r18 tires. The 285/70r17 tires with a larger diameter will register a speedometer reading of 20 mph.
However, the 275/70r18 tires with a smaller diameter will register a reading of 20.27 mph at the same actual vehicle speed. This speedometer discrepancy is due to the minor difference in tire diameters between the two sizes.
Alternative for 285/70r17
There are several alternative tire sizes available to replace 285/70R17, and you can utilize a table chart to compare them.
| Tire Size | Overall Diameter | Difference |
|---|---|---|
| 235/80R17 | 31.8″ (808 mm) | -2.9% |
| 345/55R17 | 32″ (812 mm) | -2.4% |
| 255/75R17 | 32″ (814 mm) | -2.2% |
| 275/70R17 | 32.2″ (818 mm) | -1.7% |
| 305/65R17 | 32.6″ (828 mm) | -0.5% |
| 235/85R17 | 32.8″ (832 mm) | 0% |
| 255/80R17 | 33.1″ (840 mm) | 1% |
| 295/70R17 | 33.3″ (846 mm) | 1.7% |
Alternative for 275/70r18
There are several options available if you are seeking alternative tire sizes to replace 275/70R18. You may use a table chart to compare these options.
| Tire Size | Overall Diameter | Difference |
|---|---|---|
| 305/60R18 | 32.4″ (823 mm) | -2.4% |
| 285/65R18 | 32.6″ (827 mm) | -1.9% |
| 265/70R18 | 32.6″ (829 mm) | -1.7% |
| 375/50R18 | 32.8″ (833 mm) | -1.2% |
| 295/65R18 | 33.1″ (841 mm) | -0.2% |
| 325/60R18 | 33.3″ (847 mm) | 0.5% |
| 305/65R18 | 33.6″ (853 mm) | 1.2% |
| 285/70R18 | 33.7″ (857 mm) | 1.7% |
285/70r17 vs 275/70r18
This table shows a comparison of the two tire sizes and helps you to decide which one is better for you
Our Observation
Based on the comparisons, the 285/70R17 is best suited for responsive on-road handling and improved fuel economy thanks to its shorter sidewall and narrower width. Meanwhile, the 275/70R18 excels at off-road traction and absorbs bumps better for a smoother ride thanks to its additional sidewall flex.
For mixed driving conditions, we recommend the more well-rounded 275/70R18 size – the extra ground clearance and cushioning provide versatility without sacrificing much on-road performance. Its added traction also gives more capability in rain or snow.
Meet Caitlin McCormack, a Tire Size Expert and Blogger Passionate About Everything Related to Tires. With Years of Experience in the Tire Industry, Caitlin Has Become an Expert in Tire Sizes and Their Impact on Vehicle Performance.
