-6.91%Not recommended — recalibrate the speedometer
Speedometer error
With a speedometer calibrated to 285/75R16, fitting 265/65R17 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 37.2 km/h | 25 mph | 23 mph |
| 60 km/h | 55.9 km/h | 37 mph | 35 mph |
| 80 km/h | 74.5 km/h | 50 mph | 46 mph |
| 100 km/h | 93.1 km/h | 62 mph | 58 mph |
| 120 km/h | 111.7 km/h | 75 mph | 69 mph |
Full comparison
285/75R16
Overall diameter833.9 mm · 32.83 in
Section width285 mm · 11.22 in
Sidewall height213.8 mm · 8.42 in
Circumference2619.8 mm · 103.1 in
Revolutions per mile614
Revolutions per km382
265/65R17
Overall diameter776.3 mm · 30.56 in
Section width265 mm · 10.43 in
Sidewall height172.3 mm · 6.78 in
Circumference2438.8 mm · 96.0 in
Revolutions per mile660
Revolutions per km410
-6.91%Not recommended — recalibrate the speedometer
Original
Overall diameter833.9 mm · 32.83 in
Sidewall height213.8 mm
Circumference2,619.8 mm
Revolutions / mile614.3
New
Overall diameter776.3 mm · 30.56 in
Sidewall height172.3 mm
Circumference2,438.8 mm
Revolutions / mile659.9
Speedometer & odometer error
The new tire changes overall diameter by -6.91%. With a speedometer calibrated to the original tire, that same percentage is how far the speedometer and odometer read off — a taller tire means your true speed is higher than indicated and the odometer under-counts distance.
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 37.2 km/h | 25 mph | 23 mph |
| 60 km/h | 55.9 km/h | 37 mph | 35 mph |
| 80 km/h | 74.5 km/h | 50 mph | 46 mph |
| 100 km/h | 93.1 km/h | 62 mph | 58 mph |
| 120 km/h | 111.7 km/h | 75 mph | 69 mph |
See individual specs: 285/75R16 · 265/65R17. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.