275/55R15 vs 265/60R15
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 | 275/55R15 | 265/60R15 | Change |
|---|---|---|---|
| Overall height | 26.9" | 27.5" | +2.3 % |
| Sidewall | 5.95" | 6.26" | +5.1 % |
| Section width | 275 mm | 265 mm | -3.6 % |
| Circumference | 84.5" | 86.5" | +2.3 % |
| Revs per mile | 749 | 733 | -2.3 % |
| Axle height | 13.45" | 13.76" | +7.8 mm |
| Approved rim width | 7.5–10" | 7.5–9.5" | overlap 7.5–9.5" |
Both are approved on a rim 7.5" to 9.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 275/55R15. Fit 265/60R15 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 | 92.0 mph | +2.0 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,227 on the road, so it under-counts by 227. At a true 70 mph the first turns 874 times a minute, the second 855.
What drivers reported
Nobody has filed a complaint naming 275/55R15. 265/60R15 carries 2.