255/60R15 vs 265/55R15
Going from one to the other changes the overall height by -2.1 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 255/60R15 | 265/55R15 | Change |
|---|---|---|---|
| Overall height | 27.0" | 26.5" | -2.1 % |
| Sidewall | 6.02" | 5.74" | -4.7 % |
| Section width | 255 mm | 265 mm | +3.9 % |
| Circumference | 85.0" | 83.2" | -2.1 % |
| Revs per mile | 746 | 762 | +2.1 % |
| Axle height | 13.52" | 13.24" | -7.3 mm |
| Approved rim width | 7–9.5" | 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 255/60R15. Fit 265/55R15 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.4 mph | -0.6 |
| 50 mph | 48.9 mph | -1.1 |
| 70 mph | 68.5 mph | -1.5 |
| 90 mph | 88.1 mph | -1.9 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,789 on the road, so it over-counts by 211. At a true 70 mph the first turns 870 times a minute, the second 889.
What drivers reported
255/60R15 carries 3 complaints. Nobody has filed one naming 265/55R15.