245/35R20
245/35R20 is uncommon as OEM fitment but appears as an aftermarket upsize option. At 26.75″ diameter with a 3.38″ sidewall (35% of section width), this size turns 754 revolutions per mile.
About 245/35R20
245/35R20 is less common as a factory fitment but is available as an aftermarket size, so SKU selection is narrower than mainstream OEM sizes. At 26.75″ overall diameter, 245/35R20 turns 754 revolutions per mile, which is the reference point the factory speedometer and odometer were calibrated against. The 35% aspect ratio gives it an ultra-low-profile sidewall tuned for maximum steering precision — at the cost of ride comfort and rim protection. The 20″ rim pairing is typical for luxury SUV and performance-oriented platforms, so compatible wheels are easy to source new or used. Going one step shorter to 235/35R20 drops diameter by 1.03%, which stays within the ±3% fitment safe zone for most vehicles. Stepping up to 255/35R20 adds 1.03% diameter — also inside the safe window, with marginally taller ride height. If you are shopping for a direct replacement, any tire within roughly ±0.7″ of the 26.75″ stock diameter (about ±2% in percentage terms) will keep ABS, TPMS, and odometer readings inside the vehicle's designed tolerance.
Compare with another size
275/65R18 or "33" for inch aliases245/35R20
- Diameter
- 26.75″ / 679.5mm
- Section Width
- 9.65″
- Sidewall
- 3.38″ / 85.75mm
- Circumference
- 84.04″
- Revs/Mile
- 754
235/35R20
- Diameter
- 26.48″ / 672.5mm
- Section Width
- 9.25″
- Sidewall
- 3.24″ / 82.25mm
- Circumference
- 83.18″
- Revs/Mile
- 762
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 59.38 mph (95.57 km/h). Your speedometer reads 1.03% high versus actual speed.