CarSpecsHQ

295/30R20 vs 315/30R20

315/30R20 is a safe swap for 295/30R20 by the usual ±3% rule: the diameter differs by +1.75%.

20" rim
295/30R20 26.97" · 315/30R20 27.44" · drawn to scale

Side by side

295/30R20315/30R20Difference
Overall diameter26.97"27.44"+0.47" (+1.75%)
Section width295 mm315 mm+20 mm
Sidewall3.48"3.72"+0.24"
Rim20"20"same
Circumference84.7"86.2"+1.5"
Revs per mile748735-13
Ride height——+0.24"
Speedometer reads 60 mph60.061.1+1.1 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.1 mph

With 315/30R20 on a car calibrated for 295/30R20, the speedometer reads 59.0 mph when you're really doing 60, and the odometer under-counts by 1.8%.

Speedo showsActual speed
30 mph30.5 mph
45 mph45.8 mph
60 mph61.1 mph
70 mph71.2 mph
80 mph81.4 mph

Other sizes close to 295/30R20

Questions

Can I replace 295/30R20 with 315/30R20?

315/30R20 is a safe swap for 295/30R20 by the usual ±3% rule: the diameter differs by +1.75%.

What's the difference between 295/30R20 and 315/30R20?

315/30R20 is 0.47" taller and 20 mm wider; the sidewall is +0.24". At an indicated 60 mph you'd actually be doing 61.1 mph.

Will 315/30R20 fit on 295/30R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 315 mm tire and the fender clearance.