275/60R18 vs 285/65R18
285/65R18 is outside the ±3% rule as a replacement for 275/60R18: the diameter differs by +5.14%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
Speedometer and odometer
With 285/65R18 on a car calibrated for 275/60R18, the speedometer reads 57.1 mph when you're really doing 60, and the odometer under-counts by 5.1%.
| Speedo shows | Actual speed |
|---|---|
| 30 mph | 31.5 mph |
| 45 mph | 47.3 mph |
| 60 mph | 63.1 mph |
| 70 mph | 73.6 mph |
| 80 mph | 84.1 mph |
Other sizes close to 275/60R18
- 275/60R18 vs 275/65R18+3.49%
- 275/60R18 vs 265/60R18-1.52%
- 275/60R18 vs 245/60R18-4.57%
- 275/60R18 vs 265/65R18+1.84%
- 275/60R18 vs 235/65R18-3.11%
- 275/60R18 vs 255/70R18+3.43%
- 275/60R18 vs 255/65R18+0.19%
- 275/60R18 vs 255/60R19+0.18%
- 275/60R18 vs 255/70R17+0.20%
- 275/60R18 vs 255/60R18-3.05%
- 275/60R18 vs 235/75R17-0.37%
- 275/60R18 vs 285/60R18+1.52%
Questions
Can I replace 275/60R18 with 285/65R18?
285/65R18 is outside the ±3% rule as a replacement for 275/60R18: the diameter differs by +5.14%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.
What's the difference between 275/60R18 and 285/65R18?
285/65R18 is 1.59" taller and 10 mm wider; the sidewall is +0.80". At an indicated 60 mph you'd actually be doing 63.1 mph.
Will 285/65R18 fit on 275/60R18 wheels?
Both use a 18" rim, so the wheel diameter matches; check the wheel's width range for a 285 mm tire and the fender clearance.