345/55R24 vs 335/60R24
Going from one to the other changes the overall height by +2.3 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 345/55R24 | 335/60R24 | Change |
|---|---|---|---|
| Overall height | 38.9" | 39.8" | +2.3 % |
| Sidewall | 7.47" | 7.91" | +5.9 % |
| Section width | 345 mm | 335 mm | -2.9 % |
| Circumference | 122.3" | 125.1" | +2.3 % |
| Revs per mile | 518 | 506 | -2.3 % |
| Axle height | 19.47" | 19.91" | +11.3 mm |
| Approved rim width | 9.5–12.5" | 9.5–12.5" | overlap 9.5–12.5" |
Both are approved on a rim 9.5" to 12.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 345/55R24. Fit 335/60R24 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 30.7 mph | +0.7 |
| 50 mph | 51.1 mph | +1.1 |
| 70 mph | 71.6 mph | +1.6 |
| 90 mph | 92.0 mph | +2.0 |
The odometer drifts with it. Ten thousand miles on the dial are really 10,227 on the road, so it under-counts by 227. At a true 70 mph the first turns 604 times a minute, the second 591.