295/65R22 vs 305/60R22
Going from one to the other changes the overall height by -1.9 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 295/65R22 | 305/60R22 | Change |
|---|---|---|---|
| Overall height | 37.1" | 36.4" | -1.9 % |
| Sidewall | 7.55" | 7.20" | -4.6 % |
| Section width | 295 mm | 305 mm | +3.4 % |
| Circumference | 116.5" | 114.4" | -1.9 % |
| Revs per mile | 544 | 554 | +1.9 % |
| Axle height | 18.55" | 18.20" | -8.8 mm |
| Approved rim width | 8.5–11" | 8.5–11" | overlap 8.5–11" |
Both are approved on a rim 8.5" to 11" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 295/65R22. Fit 305/60R22 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.4 mph | -0.6 |
| 50 mph | 49.1 mph | -0.9 |
| 70 mph | 68.7 mph | -1.3 |
| 90 mph | 88.3 mph | -1.7 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,814 on the road, so it over-counts by 186. At a true 70 mph the first turns 634 times a minute, the second 646.