275/55R20 vs 275/65R18
275/65R18 is 4.0 mm taller than 275/55R20 in overall diameter (+0.5%), within the usual 3% limit, so it can replace it where the wheels and clearance allow. With 275/65R18 fitted, the speedometer reads 100 km/h when you are doing 100.5 km/h.
Dimensions side by side
| 275/55R20 | 275/65R18 | |
|---|---|---|
| Overall diameter | 811 mm (31.9″) | 815 mm (32.1″) |
| Section width | 275 mm | 275 mm |
| Sidewall height | 151 mm | 179 mm |
| Rim | 20″ | 18″ |
| Revolutions per km | 392 | 391 |
| In stock | 58 tires from $195.00 | 38 tires from $181.00 |
What changes
- Overall diameter: 275/65R18 is 4.0 mm taller (+0.5%).
- Speedometer: reads 100 km/h at an actual 100.5 km/h with 275/65R18.
- Wheel size changes from 20″ to 18″: you need wheels in the new size.
- Choose a load index at least as high as the one on your door placard.
Vehicles that came with both sizes
Vehicles that use 275/55R20
Vehicles that use 275/65R18
See every alternate size for 275/55R20
Frequently asked questions
Can I use 275/65R18 instead of 275/55R20?
Usually, yes: 275/65R18 is within 3% of the overall diameter of 275/55R20 (+0.5%). Use wheels of the right size and width, match or exceed the original load index, and check clearance at full steering lock.
How much does the speedometer change between 275/55R20 and 275/65R18?
With 275/65R18 instead of 275/55R20, the speedometer shows 100 km/h when you are actually doing 100.5 km/h.
Which vehicles came with both 275/55R20 and 275/65R18?
Both sizes were original equipment, on different trims or packages, on the 2011–2024 Ford Expedition, 2019–2024 Ram 1500, 2022–2024 Jeep Wagoneer, 2024 Jeep Wagoneer L, 2007–2021 Toyota Tundra, 2006–2020 Ford F150.