CarSpecsHQ

235/50R20 vs 295/45R20

295/45R20 is outside the ±3% rule as a replacement for 235/50R20: the diameter differs by +4.10%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

20" rim
235/50R20 29.25" · 295/45R20 30.45" · drawn to scale

Side by side

235/50R20295/45R20Difference
Overall diameter29.25"30.45"+1.20" (+4.10%)
Section width235 mm295 mm+60 mm
Sidewall4.63"5.23"+0.60"
Rim20"20"same
Circumference91.9"95.7"+3.8"
Revs per mile689662-27
Ride height——+0.60"
Speedometer reads 60 mph60.062.5+2.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 62.5 mph

With 295/45R20 on a car calibrated for 235/50R20, the speedometer reads 57.6 mph when you're really doing 60, and the odometer under-counts by 4.1%.

Speedo showsActual speed
30 mph31.2 mph
45 mph46.8 mph
60 mph62.5 mph
70 mph72.9 mph
80 mph83.3 mph

Other sizes close to 235/50R20

Questions

Can I replace 235/50R20 with 295/45R20?

295/45R20 is outside the ±3% rule as a replacement for 235/50R20: the diameter differs by +4.10%, so the speedometer, odometer and ABS calibration will be off and clearance needs checking.

What's the difference between 235/50R20 and 295/45R20?

295/45R20 is 1.20" taller and 60 mm wider; the sidewall is +0.60". At an indicated 60 mph you'd actually be doing 62.5 mph.

Will 295/45R20 fit on 235/50R20 wheels?

Both use a 20" rim, so the wheel diameter matches; check the wheel's width range for a 295 mm tire and the fender clearance.