225/65R15 vs 235/60R15
Going from one to the other changes the overall height by -1.6 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 225/65R15 | 235/60R15 | Change |
|---|---|---|---|
| Overall height | 26.5" | 26.1" | -1.6 % |
| Sidewall | 5.76" | 5.55" | -3.6 % |
| Section width | 225 mm | 235 mm | +4.4 % |
| Circumference | 83.3" | 82.0" | -1.6 % |
| Revs per mile | 761 | 773 | +1.6 % |
| Axle height | 13.26" | 13.05" | -5.3 mm |
| Approved rim width | 6–8.5" | 6.5–8.5" | overlap 6.5–8.5" |
Both are approved on a rim 6.5" to 8.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 225/65R15. Fit 235/60R15 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.5 mph | -0.5 |
| 50 mph | 49.2 mph | -0.8 |
| 70 mph | 68.9 mph | -1.1 |
| 90 mph | 88.6 mph | -1.4 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,844 on the road, so it over-counts by 156. At a true 70 mph the first turns 887 times a minute, the second 901.
What drivers reported
Nobody has filed a complaint naming 225/65R15. 235/60R15 carries 4.