245/35ZR19 vs 235/40R19
235/40R19 is taller than 245/35ZR19 by 2.52% — a diameter difference of 0.65″.
What changes between 245/35ZR19 and 235/40R19
Switching from 245/35ZR19 to 235/40R19 changes overall diameter by +2.52%, a taller tire by 0.65 inches. This lands inside the ±3% fitment safe zone, so most vehicles will accept the swap without rubbing, speedometer recalibration, or ABS/TPMS complications. Section width moves by -0.40″ (245mm → 235mm), which affects contact patch and fender-well clearance. Sidewall height shifts by +0.32″: a taller sidewall softens ride quality and adds off-road bump protection, with some loss of steering crispness. Revs per mile moves by -19, which translates directly to speedometer error — at an indicated 65 mph, actual speed becomes 66.6 mph. Both sizes share the same 19″ rim, so no wheel change is required — this is a pure tire-only swap.
| Spec | 245/35ZR19 | 235/40R19 |
|---|---|---|
| Overall diameter | 25.75″ | 26.4″ |
| Section width | 9.65″ (245 mm) | 9.25″ (235 mm) |
| Sidewall height | 3.38″ (35%) | 3.7″ (40%) |
| Rim diameter | 19″ | 19″ |
| Circumference | 80.9″ | 82.94″ |
| Revs per mile | 783 | 764 |
Interactive comparison
275/65R18 or "33" for inch aliases245/35ZR19
- Diameter
- 25.75″ / 654.1mm
- Section Width
- 9.65″
- Sidewall
- 3.38″ / 85.75mm
- Circumference
- 80.9″
- Revs/Mile
- 783
235/40R19
- Diameter
- 26.4″ / 670.6mm
- Section Width
- 9.25″
- Sidewall
- 3.7″ / 94mm
- Circumference
- 82.94″
- Revs/Mile
- 764
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 61.51 mph (99 km/h). Your speedometer reads 2.52% low versus actual speed.