CarSpecsHQ

245/35R19 vs 315/30R19

315/30R19 is a safe swap for 245/35R19 by the usual ±3% rule: the diameter differs by +2.68%.

19" rim
245/35R19 25.75" · 315/30R19 26.44" · drawn to scale

Side by side

245/35R19315/30R19Difference
Overall diameter25.75"26.44"+0.69" (+2.68%)
Section width245 mm315 mm+70 mm
Sidewall3.38"3.72"+0.34"
Rim19"19"same
Circumference80.9"83.1"+2.2"
Revs per mile783763-20
Ride height——+0.34"
Speedometer reads 60 mph60.061.6+1.6 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.6 mph

With 315/30R19 on a car calibrated for 245/35R19, the speedometer reads 58.4 mph when you're really doing 60, and the odometer under-counts by 2.7%.

Speedo showsActual speed
30 mph30.8 mph
45 mph46.2 mph
60 mph61.6 mph
70 mph71.9 mph
80 mph82.1 mph

Other sizes close to 245/35R19

Questions

Can I replace 245/35R19 with 315/30R19?

315/30R19 is a safe swap for 245/35R19 by the usual ±3% rule: the diameter differs by +2.68%.

What's the difference between 245/35R19 and 315/30R19?

315/30R19 is 0.69" taller and 70 mm wider; the sidewall is +0.34". At an indicated 60 mph you'd actually be doing 61.6 mph.

Will 315/30R19 fit on 245/35R19 wheels?

Both use a 19" rim, so the wheel diameter matches; check the wheel's width range for a 315 mm tire and the fender clearance.