235/55R19 vs 225/65R17
225/65R17 has an overall diameter of 724.3 mm (28.52") compared with 741.1 mm (29.18") for 235/55R19, a difference of -16.8 mm (-2.27 %). The sidewall changes by +17.0 mm, section width by -10 mm and ride height by -8.4 mm. Using the ETRTO rolling circumference, 235/55R19 turns 442 times per kilometre and 225/65R17 turns 453 times. With 225/65R17 fitted to a car calibrated for 235/55R19, an indicated 100 km/h is a true 97.7 km/h, and the odometer records 102.3 km for every 100 km driven. This is close to the commonly quoted 3 % tolerance, so check clearance and local rules.
Full comparison
| Measurement | 235/55R19 | 225/65R17 | Difference |
|---|---|---|---|
| Section width | 235 mm | 225 mm | -10 mm |
| Sidewall height | 129.3 mm | 146.3 mm | +17.0 mm |
| Rim diameter | 19" | 17" | -2.0" |
| Overall diameter | 741.1 mm (29.18") | 724.3 mm (28.52") | -16.8 mm (-2.27 %) |
| Static circumference | 2328 mm | 2275 mm | -53 mm |
| Rolling circumference (ETRTO) | 2260 mm | 2209 mm | -51 mm |
| Revs per km | 442 | 453 | +10 |
| Ride height | -8.4 mm | ||
| Inch equivalent | 29.2×9.3R19 | 28.5×8.9R17 | |
| Approved rim widths (approx.) | 6.5″–8.5″ | 6″–7.5″ |
Speedometer error
| Speedo reads | 40 | 50 | 60 | 80 | 100 | 110 |
|---|---|---|---|---|---|---|
| Actual speed (km/h) | 39.1 | 48.9 | 58.6 | 78.2 | 97.7 | 107.5 |
| Error (km/h) | -0.9 | -1.1 | -1.4 | -1.8 | -2.3 | -2.5 |
Assumes the speedo was accurate on 235/55R19. Odometer records 102.3 km for every 100 km actually driven.
- The 225/65R17 is 16.8 mm (2.27 %) smaller in diameter, so your speedo will read high and your odometer will over-record distance.
- Section width changes by -10 mm. Check guard, strut and inner-arch clearance and that the rim width is within the approved range for the new tyre.
- Rim diameter changes from 19" to 17", so new wheels are required.
Is 225/65R17 legal in Australia? More info needed
| Overall diameter (VSB 14 LS 4.2.4) Diameter change of -16.8 mm is within the +15 mm / -26 mm allowance for a passenger car (MA/MB) (measured against the largest size the manufacturer designates for the model). | OK |
| Speedometer (ADR 18/03) A smaller tyre makes the speedo read high: at an indicated 100 km/h you would be doing 97.7 km/h (over-read 2.3 km/h; ADR 18 allows up to 13.8 km/h at that speed). | OK |
| Load index (tyre placard / ADR 42) Enter the placard load index and the replacement tyre load index to check. | ? |
| Speed rating (tyre placard / ADR 42) Enter the placard speed rating and the replacement tyre speed rating to check. | ? |
Frequently asked
Can I fit 225/65R17 instead of 235/55R19?
Overall diameter changes by -16.8 mm (-2.27 %). That is close to the 3 % rule of thumb; it may fit, but check guard, strut and brake clearance and your local rules. In Australia VSB 14 allows up to +15 mm for passenger cars and +50 mm for 4WDs/goods vehicles without certification.
How much will my speedo be out with 225/65R17?
Your speedo will read high by about 2.27 %. At an indicated 100 km/h you would actually be travelling 97.7 km/h, and at 110 km/h about 107.5 km/h.
What is the rolling circumference of 225/65R17?
Static circumference is 2275 mm; the ETRTO rolling circumference under load is about 2209 mm, which is 453 revolutions per kilometre.
225/65R17 in inches
225/65R17 is approximately 28.5×8.9R17: 28.5" tall, 8.9" wide, on a 17" rim, with a 5.8" sidewall.
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