225/65R22 vs 245/55R22
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 | 225/65R22 | 245/55R22 | Change |
|---|---|---|---|
| Overall height | 33.5" | 32.6" | -2.7 % |
| Sidewall | 5.76" | 5.31" | -7.9 % |
| Section width | 225 mm | 245 mm | +8.9 % |
| Circumference | 105.3" | 102.4" | -2.7 % |
| Revs per mile | 602 | 618 | +2.7 % |
| Axle height | 16.76" | 16.31" | -11.5 mm |
| Approved rim width | 6–8.5" | 7–9" | overlap 7–8.5" |
Both are approved on a rim 7" to 8.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 225/65R22. Fit 245/55R22 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.2 mph | -0.8 |
| 50 mph | 48.6 mph | -1.4 |
| 70 mph | 68.1 mph | -1.9 |
| 90 mph | 87.6 mph | -2.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,730 on the road, so it over-counts by 270. At a true 70 mph the first turns 702 times a minute, the second 722.