CarSpecsHQ

255/30R19 vs 245/35R19

245/35R19 is a safe swap for 255/30R19 by the usual ±3% rule: the diameter differs by +2.91%.

19" rim
255/30R19 25.02" · 245/35R19 25.75" · drawn to scale

Side by side

255/30R19245/35R19Difference
Overall diameter25.02"25.75"+0.73" (+2.91%)
Section width255 mm245 mm-10 mm
Sidewall3.01"3.38"+0.36"
Rim19"19"same
Circumference78.6"80.9"+2.3"
Revs per mile806783-23
Ride height——+0.36"
Speedometer reads 60 mph60.061.7+1.7 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.7 mph

With 245/35R19 on a car calibrated for 255/30R19, the speedometer reads 58.3 mph when you're really doing 60, and the odometer under-counts by 2.9%.

Speedo showsActual speed
30 mph30.9 mph
45 mph46.3 mph
60 mph61.7 mph
70 mph72.0 mph
80 mph82.3 mph

Other sizes close to 255/30R19

Questions

Can I replace 255/30R19 with 245/35R19?

245/35R19 is a safe swap for 255/30R19 by the usual ±3% rule: the diameter differs by +2.91%.

What's the difference between 255/30R19 and 245/35R19?

245/35R19 is 0.73" taller and 10 mm narrower; the sidewall is +0.36". At an indicated 60 mph you'd actually be doing 61.7 mph.

Will 245/35R19 fit on 255/30R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 245 mm tire and the fender clearance.