CarSpecsHQ

255/45R19 vs 295/35R20

295/35R20 is a safe swap for 255/45R19 by the usual ±3% rule: the diameter differs by +0.34%.

19" → 20"
255/45R19 28.04" · 295/35R20 28.13" · drawn to scale

Side by side

255/45R19295/35R20Difference
Overall diameter28.04"28.13"+0.09" (+0.34%)
Section width255 mm295 mm+40 mm
Sidewall4.52"4.06"-0.45"
Rim19"20"+1"
Circumference88.1"88.4"+0.3"
Revs per mile719717-2
Ride height——+0.05"
Speedometer reads 60 mph60.060.2+0.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.2 mph

With 295/35R20 on a car calibrated for 255/45R19, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.3%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.2 mph
70 mph70.2 mph
80 mph80.3 mph

Other sizes close to 255/45R19

Questions

Can I replace 255/45R19 with 295/35R20?

295/35R20 is a safe swap for 255/45R19 by the usual ±3% rule: the diameter differs by +0.34%.

What's the difference between 255/45R19 and 295/35R20?

295/35R20 is 0.09" taller and 40 mm wider; the sidewall is -0.45". At an indicated 60 mph you'd actually be doing 60.2 mph.

Will 295/35R20 fit on 255/45R19 wheels?

No — 255/45R19 needs a 19" wheel and 295/35R20 a 20" wheel. This is a plus/minus-size swap that changes wheels too.