225/70R14 vs 235/70R14
Going from one to the other changes the overall height by +2.1 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 225/70R14 | 235/70R14 | Change |
|---|---|---|---|
| Overall height | 26.4" | 27.0" | +2.1 % |
| Sidewall | 6.20" | 6.48" | +4.4 % |
| Section width | 225 mm | 235 mm | +4.4 % |
| Circumference | 82.9" | 84.7" | +2.1 % |
| Revs per mile | 764 | 748 | -2.1 % |
| Axle height | 13.20" | 13.48" | +7.0 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 225/70R14. Fit 235/70R14 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.6 mph | +0.6 |
| 50 mph | 51.0 mph | +1.0 |
| 70 mph | 71.5 mph | +1.5 |
| 90 mph | 91.9 mph | +1.9 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,209 on the road, so it under-counts by 209. At a true 70 mph the first turns 891 times a minute, the second 873.
What drivers reported
225/70R14 carries 20 complaints and 1 deaths. Nobody has filed one naming 235/70R14.