225/65R16 vs 205/75R16
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 | 225/65R16 | 205/75R16 | Change |
|---|---|---|---|
| Overall height | 27.5" | 28.1" | +2.1 % |
| Sidewall | 5.76" | 6.05" | +5.1 % |
| Section width | 225 mm | 205 mm | -8.9 % |
| Circumference | 86.4" | 88.3" | +2.1 % |
| Revs per mile | 733 | 718 | -2.1 % |
| Axle height | 13.76" | 14.05" | +7.5 mm |
| Approved rim width | 6–8.5" | 5.5–7.5" | overlap 6–7.5" |
Both are approved on a rim 6" to 7.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 225/65R16. Fit 205/75R16 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.6 mph | +0.6 |
| 50 mph | 51.1 mph | +1.1 |
| 70 mph | 71.5 mph | +1.5 |
| 90 mph | 91.9 mph | +1.9 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,215 on the road, so it under-counts by 215. At a true 70 mph the first turns 855 times a minute, the second 837.
What drivers reported
225/65R16 carries 23 complaints. Nobody has filed one naming 205/75R16.