315/35R19 vs 335/30R19
Going from one to the other changes the overall height by -2.8 %. That is inside the 3% band, so it fits and the speedometer stays close.
Side by side
| Measure | 315/35R19 | 335/30R19 | Change |
|---|---|---|---|
| Overall height | 27.7" | 26.9" | -2.8 % |
| Sidewall | 4.34" | 3.96" | -8.8 % |
| Section width | 315 mm | 335 mm | +6.3 % |
| Circumference | 87.0" | 84.6" | -2.8 % |
| Revs per mile | 729 | 749 | +2.8 % |
| Axle height | 13.84" | 13.46" | -9.8 mm |
| Approved rim width | 8.5–11.5" | 9.5–12.5" | overlap 9.5–11.5" |
Both are approved on a rim 9.5" to 11.5" wide. If yours is in that band, this is a tire change and nothing else.
What the speedometer will say
Calibrated for 315/35R19. Fit 335/30R19 and the needle stops telling the truth.
| Needle says | You are doing | Out by |
|---|---|---|
| 30 mph | 29.2 mph | -0.8 |
| 50 mph | 48.6 mph | -1.4 |
| 70 mph | 68.1 mph | -1.9 |
| 90 mph | 87.5 mph | -2.5 |
The odometer drifts with it. Ten thousand miles on the dial are really 9,723 on the road, so it over-counts by 277. At a true 70 mph the first turns 850 times a minute, the second 874.