285/30R22 vs 275/35R22
Going from one to the other changes the overall height by +2.9 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 285/30R22 | 275/35R22 | Change |
|---|---|---|---|
| Overall height | 28.7" | 29.6" | +2.9 % |
| Sidewall | 3.37" | 3.79" | +12.6 % |
| Section width | 285 mm | 275 mm | -3.5 % |
| Circumference | 90.3" | 92.9" | +2.9 % |
| Revs per mile | 702 | 682 | -2.9 % |
| Axle height | 14.37" | 14.79" | +10.8 mm |
| Approved rim width | 8–10.5" | 7.5–10" | overlap 8–10" |
Both are approved on a rim 8" to 10" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 285/30R22. Fit 275/35R22 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.9 mph | +0.9 |
| 50 mph | 51.5 mph | +1.5 |
| 70 mph | 72.1 mph | +2.1 |
| 90 mph | 92.7 mph | +2.7 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,295 on the road, so it under-counts by 295. At a true 70 mph the first turns 819 times a minute, the second 795.