265/70R17 vs 285/70R17 at a glance
| Measure | 265/70R17 (current) | 285/70R17 (new) | Difference |
|---|---|---|---|
| Overall height | 31.61 in | 32.71 in | +1.10 in (+3.49%) |
| Width | 10.43 in (265 mm) | 11.22 in (285 mm) | +20 mm |
| Sidewall | 7.30 in | 7.85 in | +0.55 in |
| Wheel | 17 in | 17 in | +0 in |
| Circumference | 99.3 in | 102.8 in | +3.5 in |
| Revs per mile | 638.1 | 616.6 | −21.5 |
Verdict: check clearance and speedometer
Over 3% and up to 5%: worth checking clearance, the speedometer and gearing before you buy. Going from 265/70R17 to 285/70R17 is a 3.5% increase in overall height (+1.10 in), and the vehicle sits about 0.55 in higher. The tire is 20 mm wider. 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 | 56.9 mph | +1.9 mph |
| 60 mph | 62.1 mph | +2.1 mph |
| 65 mph | 67.3 mph | +2.3 mph |
| 70 mph | 72.4 mph | +2.4 mph |
| 75 mph | 77.6 mph | +2.6 mph |
Odometer: 1,000 indicated miles is 1,035 real miles, and 10,000 is 10,349.
The math
265/70R17: 17 + 2 × (265 × 70% ÷ 25.4) = 31.61 in. 285/70R17: 17 + 2 × (285 × 70% ÷ 25.4) = 32.71 in. Change = 32.71 ÷ 31.61 − 1 = +3.49%. True speed at 60 = 60 × 32.71 ÷ 31.61 = 62.09 mph.
Check next
- Regear and RPM at cruise for this swap
- Speedometer and odometer correction
- Other sizes within ±3% of 265/70R17
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: 265/70R17 · 285/70R17. More swaps: all tire size comparisons.