205/70R19 vs 205/65R19
Going from one to the other changes the overall height by -2.7 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 205/70R19 | 205/65R19 | Change |
|---|---|---|---|
| Overall height | 30.3" | 29.5" | -2.7 % |
| Sidewall | 5.65" | 5.25" | -7.1 % |
| Section width | 205 mm | 205 mm | 0.0 % |
| Circumference | 95.2" | 92.7" | -2.7 % |
| Revs per mile | 666 | 684 | +2.7 % |
| Axle height | 15.15" | 14.75" | -10.3 mm |
| Approved rim width | 5.5–7.5" | 5.5–7.5" | overlap 5.5–7.5" |
Both are approved on a rim 5.5" 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 205/70R19. Fit 205/65R19 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.2 mph | -0.8 |
| 50 mph | 48.7 mph | -1.3 |
| 70 mph | 68.1 mph | -1.9 |
| 90 mph | 87.6 mph | -2.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,734 on the road, so it over-counts by 266. At a true 70 mph the first turns 777 times a minute, the second 798.