155/75R13 vs 165/75R13
Going from one to the other changes the overall height by +2.7 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 155/75R13 | 165/75R13 | Change |
|---|---|---|---|
| Overall height | 22.2" | 22.7" | +2.7 % |
| Sidewall | 4.58" | 4.87" | +6.5 % |
| Section width | 155 mm | 165 mm | +6.5 % |
| Circumference | 69.6" | 71.5" | +2.7 % |
| Revs per mile | 910 | 887 | -2.7 % |
| Axle height | 11.08" | 11.37" | +7.5 mm |
| Approved rim width | 4–5.5" | 4.5–6" | 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 155/75R13. Fit 165/75R13 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.8 mph | +0.8 |
| 50 mph | 51.3 mph | +1.3 |
| 70 mph | 71.9 mph | +1.9 |
| 90 mph | 92.4 mph | +2.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,267 on the road, so it under-counts by 267. At a true 70 mph the first turns 1062 times a minute, the second 1035.