265/30R16 vs 245/35R16
Going from one to the other changes the overall height by +2.2 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 265/30R16 | 245/35R16 | Change |
|---|---|---|---|
| Overall height | 22.3" | 22.8" | +2.2 % |
| Sidewall | 3.13" | 3.38" | +7.9 % |
| Section width | 265 mm | 245 mm | -7.5 % |
| Circumference | 69.9" | 71.5" | +2.2 % |
| Revs per mile | 906 | 886 | -2.2 % |
| Axle height | 11.13" | 11.38" | +6.3 mm |
| Approved rim width | 7.5–9.5" | 7–9" | overlap 7.5–9" |
Both are approved on a rim 7.5" to 9" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 265/30R16. Fit 245/35R16 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.7 mph | +0.7 |
| 50 mph | 51.1 mph | +1.1 |
| 70 mph | 71.5 mph | +1.5 |
| 90 mph | 92.0 mph | +2.0 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,221 on the road, so it under-counts by 221. At a true 70 mph the first turns 1057 times a minute, the second 1034.