215/85R19 vs 225/85R19
Going from one to the other changes the overall height by +2.0 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 215/85R19 | 225/85R19 | Change |
|---|---|---|---|
| Overall height | 33.4" | 34.1" | +2.0 % |
| Sidewall | 7.19" | 7.53" | +4.7 % |
| Section width | 215 mm | 225 mm | +4.7 % |
| Circumference | 104.9" | 107.0" | +2.0 % |
| Revs per mile | 604 | 592 | -2.0 % |
| Axle height | 16.69" | 17.03" | +8.5 mm |
| Approved rim width | 6–8" | 6–8.5" | overlap 6–8" |
Both are approved on a rim 6" to 8" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 215/85R19. Fit 225/85R19 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.6 mph | +0.6 |
| 50 mph | 51.0 mph | +1.0 |
| 70 mph | 71.4 mph | +1.4 |
| 90 mph | 91.8 mph | +1.8 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,200 on the road, so it under-counts by 200. At a true 70 mph the first turns 705 times a minute, the second 691.