205/75R17 vs 225/70R17
Going from one to the other changes the overall height by +1.0 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 205/75R17 | 225/70R17 | Change |
|---|---|---|---|
| Overall height | 29.1" | 29.4" | +1.0 % |
| Sidewall | 6.05" | 6.20" | +2.4 % |
| Section width | 205 mm | 225 mm | +9.8 % |
| Circumference | 91.4" | 92.4" | +1.0 % |
| Revs per mile | 693 | 686 | -1.0 % |
| Axle height | 14.55" | 14.70" | +3.8 mm |
| Approved rim width | 5.5–7.5" | 6–8.5" | 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 205/75R17. Fit 225/70R17 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.3 mph | +0.3 |
| 50 mph | 50.5 mph | +0.5 |
| 70 mph | 70.7 mph | +0.7 |
| 90 mph | 90.9 mph | +0.9 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,101 on the road, so it under-counts by 101. At a true 70 mph the first turns 808 times a minute, the second 800.
What drivers reported
Nobody has filed a complaint naming 205/75R17. 225/70R17 carries 8.