195/45R17 vs 215/40R17
Going from one to the other changes the overall height by -0.6 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 195/45R17 | 215/40R17 | Change |
|---|---|---|---|
| Overall height | 23.9" | 23.8" | -0.6 % |
| Sidewall | 3.45" | 3.39" | -2.0 % |
| Section width | 195 mm | 215 mm | +10.3 % |
| Circumference | 75.1" | 74.7" | -0.6 % |
| Revs per mile | 844 | 848 | +0.6 % |
| Axle height | 11.95" | 11.89" | -1.8 mm |
| Approved rim width | 5.5–7" | 6–8" | overlap 6–7" |
Both are approved on a rim 6" to 7" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 195/45R17. Fit 215/40R17 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.8 mph | -0.2 |
| 50 mph | 49.7 mph | -0.3 |
| 70 mph | 69.6 mph | -0.4 |
| 90 mph | 89.5 mph | -0.5 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,942 on the road, so it over-counts by 58. At a true 70 mph the first turns 984 times a minute, the second 990.
What drivers reported
Nobody has filed a complaint naming 195/45R17. 215/40R17 carries 2.