155/70R14 vs 175/60R14
Going from one to the other changes the overall height by -1.2 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 155/70R14 | 175/60R14 | Change |
|---|---|---|---|
| Overall height | 22.5" | 22.3" | -1.2 % |
| Sidewall | 4.27" | 4.13" | -3.2 % |
| Section width | 155 mm | 175 mm | +12.9 % |
| Circumference | 70.8" | 70.0" | -1.2 % |
| Revs per mile | 895 | 906 | +1.2 % |
| Axle height | 11.27" | 11.13" | -3.5 mm |
| Approved rim width | 4–5.5" | 5–6" | overlap 5–5.5" |
Both are approved on a rim 5" to 5.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 155/70R14. Fit 175/60R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.6 mph | -0.4 |
| 50 mph | 49.4 mph | -0.6 |
| 70 mph | 69.1 mph | -0.9 |
| 90 mph | 88.9 mph | -1.1 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,878 on the road, so it over-counts by 122. At a true 70 mph the first turns 1044 times a minute, the second 1057.