225/85R17 vs 215/85R17
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 | 225/85R17 | 215/85R17 | Change |
|---|---|---|---|
| Overall height | 32.1" | 31.4" | -2.1 % |
| Sidewall | 7.53" | 7.19" | -4.4 % |
| Section width | 225 mm | 215 mm | -4.4 % |
| Circumference | 100.7" | 98.6" | -2.1 % |
| Revs per mile | 629 | 643 | +2.1 % |
| Axle height | 16.03" | 15.69" | -8.5 mm |
| Approved rim width | 6–8.5" | 6–8" | 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 225/85R17. Fit 215/85R17 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.4 mph | -0.6 |
| 50 mph | 49.0 mph | -1.0 |
| 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 9,791 on the road, so it over-counts by 209. At a true 70 mph the first turns 734 times a minute, the second 750.
What drivers reported
225/85R17 carries 1 complaints. Nobody has filed one naming 215/85R17.