ElpiAuto245/75R17 vs 265/70R17
265/70R17 is 0.14″ (4 mm) taller than 245/75R17, a 0.4% difference in overall diameter — comfortably inside the ±3% band most fitment guides use, so it swaps straight across for gearing and the speedometer.
| Measurement | 245/75R17 | 265/70R17 | Difference | % |
|---|---|---|---|---|
| Overall diameter | 31.47″ | 31.61″ | +0.14″ | +0.4% |
| Section width | 9.65″ | 10.43″ | +0.79″ | +8.2% |
| Sidewall height | 7.23″ | 7.30″ | +0.07″ | +1.0% |
| Circumference | 98.86″ | 99.29″ | +0.43″ | +0.4% |
| Revs per mile | 640.9 | 638.1 | −2.8 | −0.4% |
| Revs per km | 398.2 | 396.5 | −1.7 | −0.4% |
Speedometer: with 245/75R17 as the original, 265/70R17 makes an indicated 60 mph really about 60.3 mph, and the axle sits ~0.07″ higher.
Reading this comparison
The overall diameter is what matters here: 265/70R17 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.