195/60R17 vs 185/60R17
Going from one to the other changes the overall height by -1.8 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 195/60R17 | 185/60R17 | Change |
|---|---|---|---|
| Overall height | 26.2" | 25.7" | -1.8 % |
| Sidewall | 4.61" | 4.37" | -5.1 % |
| Section width | 195 mm | 185 mm | -5.1 % |
| Circumference | 82.3" | 80.9" | -1.8 % |
| Revs per mile | 769 | 784 | +1.8 % |
| Axle height | 13.11" | 12.87" | -6.0 mm |
| Approved rim width | 5.5–7" | 5–6.5" | overlap 5.5–6.5" |
Both are approved on a rim 5.5" to 6.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 195/60R17. Fit 185/60R17 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.5 mph | -0.5 |
| 50 mph | 49.1 mph | -0.9 |
| 70 mph | 68.7 mph | -1.3 |
| 90 mph | 88.4 mph | -1.6 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,820 on the road, so it over-counts by 180. At a true 70 mph the first turns 898 times a minute, the second 914.
What drivers reported
195/60R17 carries 1 complaints. Nobody has filed one naming 185/60R17.