ElpiAuto265/75R17 vs 285/70R17
285/70R17 is 0.06″ (2 mm) taller than 265/75R17, a 0.2% difference in overall diameter — comfortably inside the ±3% band most fitment guides use, so it swaps straight across for gearing and the speedometer.
| Measurement | 265/75R17 | 285/70R17 | Difference | % |
|---|---|---|---|---|
| Overall diameter | 32.65″ | 32.71″ | +0.06″ | +0.2% |
| Section width | 10.43″ | 11.22″ | +0.79″ | +7.5% |
| Sidewall height | 7.82″ | 7.85″ | +0.03″ | +0.4% |
| Circumference | 102.57″ | 102.76″ | +0.19″ | +0.2% |
| Revs per mile | 617.7 | 616.6 | −1.1 | −0.2% |
| Revs per km | 383.8 | 383.1 | −0.7 | −0.2% |
Speedometer: with 265/75R17 as the original, 285/70R17 makes an indicated 60 mph really about 60.1 mph, and the axle sits ~0.03″ higher.
Reading this comparison
The overall diameter is what matters here: 285/70R17 is the taller tire. It sets ride height, gearing and how far the tire travels per revolution — which is what the speedometer and odometer count. Width and sidewall change fit and feel (a wider tire needs a wider wheel and more clearance; a shorter sidewall sharpens steering) but not the gearing.
Figures are geometric estimates from the size codes; real moulded tires vary by brand by 1–3%. Confirm load rating, wheel width and physical clearance on your vehicle before fitting. To compare any other two sizes, use the tire size comparison tool; to decode one size and see what else fits its wheel, the tire size calculator.