+0.26%Safe swap — speedometer error is minor
Speedometer error
With a speedometer calibrated to 235/75R15, fitting 235/70R16 makes it read as follows:
| Speedo shows | True speed | Speedo shows | True speed |
|---|---|---|---|
| 40 km/h | 40.1 km/h | 25 mph | 25 mph |
| 60 km/h | 60.2 km/h | 37 mph | 37 mph |
| 80 km/h | 80.2 km/h | 50 mph | 50 mph |
| 100 km/h | 100.3 km/h | 62 mph | 62 mph |
| 120 km/h | 120.3 km/h | 75 mph | 75 mph |
Full comparison
235/75R15
Overall diameter733.5 mm · 28.88 in
Section width235 mm · 9.25 in
Sidewall height176.3 mm · 6.94 in
Circumference2304.4 mm · 90.7 in
Revolutions per mile698
Revolutions per km434
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
+0.26%Safe swap — speedometer error is minor
Original
Overall diameter733.5 mm · 28.88 in
Sidewall height176.3 mm
Circumference2,304.4 mm
Revolutions / mile698.4
New
Overall diameter735.4 mm · 28.95 in
Sidewall height164.5 mm
Circumference2,310.3 mm
Revolutions / mile696.6
Speedometer & odometer error
The new tire changes overall diameter by +0.26%. 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 | 40.1 km/h | 25 mph | 25 mph |
| 60 km/h | 60.2 km/h | 37 mph | 37 mph |
| 80 km/h | 80.2 km/h | 50 mph | 50 mph |
| 100 km/h | 100.3 km/h | 62 mph | 62 mph |
| 120 km/h | 120.3 km/h | 75 mph | 75 mph |
See individual specs: 235/75R15 · 235/70R16. A change this size can affect ABS/speed calibration — see wheel-speed codes if a light appears.