285/60R18 vs 285/65R18 at a glance
| Measure | 285/60R18 (current) | 285/65R18 (new) | Difference |
|---|---|---|---|
| Overall height | 31.46 in | 32.59 in | +1.12 in (+3.57%) |
| Width | 11.22 in (285 mm) | 11.22 in (285 mm) | +0 mm |
| Sidewall | 6.73 in | 7.29 in | +0.56 in |
| Wheel | 18 in | 18 in | +0 in |
| Circumference | 98.8 in | 102.4 in | +3.5 in |
| Revs per mile | 641.0 | 618.9 | −22.1 |
Verdict: check clearance and speedometer
Over 3% and up to 5%: worth checking clearance, the speedometer and gearing before you buy. Going from 285/60R18 to 285/65R18 is a 3.6% increase in overall height (+1.12 in), and the vehicle sits about 0.56 in higher. The tire is the same width. The 3% rule of thumb comes from Discount Tire and 1010tires; it is not a guarantee of fit.
True speed and odometer
| Speedometer shows | You are really doing | Difference |
|---|---|---|
| 35 mph | 36.2 mph | +1.2 mph |
| 45 mph | 46.6 mph | +1.6 mph |
| 55 mph | 57.0 mph | +2.0 mph |
| 60 mph | 62.1 mph | +2.1 mph |
| 65 mph | 67.3 mph | +2.3 mph |
| 70 mph | 72.5 mph | +2.5 mph |
| 75 mph | 77.7 mph | +2.7 mph |
Odometer: 1,000 indicated miles is 1,036 real miles, and 10,000 is 10,357.
The math
285/60R18: 18 + 2 × (285 × 60% ÷ 25.4) = 31.46 in. 285/65R18: 18 + 2 × (285 × 65% ÷ 25.4) = 32.59 in. Change = 32.59 ÷ 31.46 − 1 = +3.57%. True speed at 60 = 60 × 32.59 ÷ 31.46 = 62.14 mph.
Check next
- Regear and RPM at cruise for this swap
- Speedometer and odometer correction
- Other sizes within ±3% of 285/60R18
Calculated from the size alone. Real tires vary a little by brand and model, and the loaded radius is a bit smaller. Confirm the wheel width range, clearance, load index and speed rating for your vehicle. See how to read a tire size, the load index chart and the speed rating chart.
Size pages: 285/60R18 · 285/65R18. More swaps: all tire size comparisons.