245/65R19 vs 255/60R19
Going from one to the other changes the overall height by -1.6 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 245/65R19 | 255/60R19 | Change |
|---|---|---|---|
| Overall height | 31.5" | 31.0" | -1.6 % |
| Sidewall | 6.27" | 6.02" | -3.9 % |
| Section width | 245 mm | 255 mm | +4.1 % |
| Circumference | 99.1" | 97.5" | -1.6 % |
| Revs per mile | 639 | 650 | +1.6 % |
| Axle height | 15.77" | 15.52" | -6.3 mm |
| Approved rim width | 7–9" | 7–9.5" | overlap 7–9" |
Both are approved on a rim 7" to 9" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 245/65R19. Fit 255/60R19 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.5 mph | -0.5 |
| 50 mph | 49.2 mph | -0.8 |
| 70 mph | 68.9 mph | -1.1 |
| 90 mph | 88.6 mph | -1.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,844 on the road, so it over-counts by 156. At a true 70 mph the first turns 746 times a minute, the second 758.
What drivers reported
Nobody has filed a complaint naming 245/65R19. 255/60R19 carries 9.