215/75R14 vs 235/65R14
Going from one to the other changes the overall height by -2.5 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 215/75R14 | 235/65R14 | Change |
|---|---|---|---|
| Overall height | 26.7" | 26.0" | -2.5 % |
| Sidewall | 6.35" | 6.01" | -5.3 % |
| Section width | 215 mm | 235 mm | +9.3 % |
| Circumference | 83.9" | 81.8" | -2.5 % |
| Revs per mile | 755 | 775 | +2.5 % |
| Axle height | 13.35" | 13.01" | -8.5 mm |
| Approved rim width | 6–8" | 6.5–8.5" | overlap 6.5–8" |
Both are approved on a rim 6.5" to 8" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 215/75R14. Fit 235/65R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.2 mph | -0.8 |
| 50 mph | 48.7 mph | -1.3 |
| 70 mph | 68.2 mph | -1.8 |
| 90 mph | 87.7 mph | -2.3 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,749 on the road, so it over-counts by 251. At a true 70 mph the first turns 881 times a minute, the second 904.
What drivers reported
215/75R14 carries 11 complaints. Nobody has filed one naming 235/65R14.