135/70R14 vs 155/65R14
Going from one to the other changes the overall height by +2.3 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 135/70R14 | 155/65R14 | Change |
|---|---|---|---|
| Overall height | 21.4" | 21.9" | +2.3 % |
| Sidewall | 3.72" | 3.97" | +6.6 % |
| Section width | 135 mm | 155 mm | +14.8 % |
| Circumference | 67.4" | 68.9" | +2.3 % |
| Revs per mile | 941 | 920 | -2.3 % |
| Axle height | 10.72" | 10.97" | +6.3 mm |
| Approved rim width | 3.5–5" | 4–5.5" | overlap 4–5" |
Both are approved on a rim 4" to 5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 135/70R14. Fit 155/65R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.7 mph | +0.7 |
| 50 mph | 51.1 mph | +1.1 |
| 70 mph | 71.6 mph | +1.6 |
| 90 mph | 92.1 mph | +2.1 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,230 on the road, so it under-counts by 230. At a true 70 mph the first turns 1097 times a minute, the second 1073.