CarSpecsHQ

245/45R19 vs 275/45R19

275/45R19 is outside the ±3% rule as a replacement for 245/45R19: the diameter differs by +3.84%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

19" rim
245/45R19 27.68" · 275/45R19 28.74" · drawn to scale

Side by side

245/45R19275/45R19Difference
Overall diameter27.68"28.74"+1.06" (+3.84%)
Section width245 mm275 mm+30 mm
Sidewall4.34"4.87"+0.53"
Rim19"19"same
Circumference87.0"90.3"+3.3"
Revs per mile729702-27
Ride height——+0.53"
Speedometer reads 60 mph60.062.3+2.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.3 mph

With 275/45R19 on a car calibrated for 245/45R19, the speedometer reads 57.8 mph when you're really doing 60, and the odometer under-counts by 3.8%.

Speedo showsActual speed
30 mph31.2 mph
45 mph46.7 mph
60 mph62.3 mph
70 mph72.7 mph
80 mph83.1 mph

Other sizes close to 245/45R19

Questions

Can I replace 245/45R19 with 275/45R19?

275/45R19 is outside the ±3% rule as a replacement for 245/45R19: the diameter differs by +3.84%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 245/45R19 and 275/45R19?

275/45R19 is 1.06" taller and 30 mm wider; the sidewall is +0.53". At an indicated 60 mph you'd actually be doing 62.3 mph.

Will 275/45R19 fit on 245/45R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 275 mm tire and the fender clearance.