165/55R14 vs 155/60R14
Going from one to the other changes the overall height by +0.8 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 165/55R14 | 155/60R14 | Change |
|---|---|---|---|
| Overall height | 21.1" | 21.3" | +0.8 % |
| Sidewall | 3.57" | 3.66" | +2.5 % |
| Section width | 165 mm | 155 mm | -6.1 % |
| Circumference | 66.4" | 67.0" | +0.8 % |
| Revs per mile | 954 | 946 | -0.8 % |
| Axle height | 10.57" | 10.66" | +2.3 mm |
| Approved rim width | 4.5–6" | 4–5.5" | overlap 4.5–5.5" |
Both are approved on a rim 4.5" 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 165/55R14. Fit 155/60R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.3 mph | +0.3 |
| 50 mph | 50.4 mph | +0.4 |
| 70 mph | 70.6 mph | +0.6 |
| 90 mph | 90.8 mph | +0.8 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,084 on the road, so it under-counts by 84. At a true 70 mph the first turns 1113 times a minute, the second 1103.