+5.24%Not recommended — recalibrate the speedometer
Speedometer error
With a speedometer calibrated to 235/70R16, fitting 245/75R16 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 42.1 km/h | 25 mph | 26 mph |
| 60 km/h | 63.1 km/h | 37 mph | 39 mph |
| 80 km/h | 84.2 km/h | 50 mph | 52 mph |
| 100 km/h | 105.2 km/h | 62 mph | 65 mph |
| 120 km/h | 126.3 km/h | 75 mph | 78 mph |
Full comparison
235/70R16
Overall diameter735.4 mm · 28.95 in
Section width235 mm · 9.25 in
Sidewall height164.5 mm · 6.48 in
Circumference2310.3 mm · 91.0 in
Revolutions per mile697
Revolutions per km433
245/75R16
Overall diameter773.9 mm · 30.47 in
Section width245 mm · 9.65 in
Sidewall height183.8 mm · 7.23 in
Circumference2431.3 mm · 95.7 in
Revolutions per mile662
Revolutions per km411
+5.24%Not recommended — recalibrate the speedometer
Original
Overall diameter735.4 mm · 28.95 in
Sidewall height164.5 mm
Circumference2,310.3 mm
Revolutions / mile696.6
New
Overall diameter773.9 mm · 30.47 in
Sidewall height183.8 mm
Circumference2,431.3 mm
Revolutions / mile661.9
Speedometer & odometer error
The new tire changes overall diameter by +5.24%. 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 | 42.1 km/h | 25 mph | 26 mph |
| 60 km/h | 63.1 km/h | 37 mph | 39 mph |
| 80 km/h | 84.2 km/h | 50 mph | 52 mph |
| 100 km/h | 105.2 km/h | 62 mph | 65 mph |
| 120 km/h | 126.3 km/h | 75 mph | 78 mph |
See individual specs: 235/70R16 · 245/75R16. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.