265/75R19.5 vs 265/70R19.5
Going from one to the other changes the overall height by -3.0 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 265/75R19.5 | 265/70R19.5 | Change |
|---|---|---|---|
| Overall height | 35.1" | 34.1" | -3.0 % |
| Sidewall | 7.82" | 7.30" | -6.7 % |
| Section width | 265 mm | 265 mm | 0.0 % |
| Circumference | 110.4" | 107.1" | -3.0 % |
| Revs per mile | 574 | 591 | +3.0 % |
| Axle height | 17.57" | 17.05" | -13.3 mm |
| Approved rim width | 7.5–9.5" | 7.5–9.5" | overlap 7.5–9.5" |
Both are approved on a rim 7.5" to 9.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 265/75R19.5. Fit 265/70R19.5 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.1 mph | -0.9 |
| 50 mph | 48.5 mph | -1.5 |
| 70 mph | 67.9 mph | -2.1 |
| 90 mph | 87.3 mph | -2.7 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,703 on the road, so it over-counts by 297. At a true 70 mph the first turns 669 times a minute, the second 690.
What drivers reported
Nobody has filed a complaint naming 265/75R19.5. 265/70R19.5 carries 1.