CarSpecsHQ

335/30R18 vs 255/35R19

255/35R19 is a safe swap for 335/30R18 by the usual ±3% rule: the diameter differs by +0.44%.

18" → 19"
335/30R18 25.91" · 255/35R19 26.03" · drawn to scale

Side by side

335/30R18255/35R19Difference
Overall diameter25.91"26.03"+0.11" (+0.44%)
Section width335 mm255 mm-80 mm
Sidewall3.96"3.51"-0.44"
Rim18"19"+1"
Circumference81.4"81.8"+0.4"
Revs per mile778775-3
Ride height——+0.06"
Speedometer reads 60 mph60.060.3+0.3 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.3 mph

With 255/35R19 on a car calibrated for 335/30R18, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.4%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.3 mph
70 mph70.3 mph
80 mph80.4 mph

Other sizes close to 335/30R18

Questions

Can I replace 335/30R18 with 255/35R19?

255/35R19 is a safe swap for 335/30R18 by the usual ±3% rule: the diameter differs by +0.44%.

What's the difference between 335/30R18 and 255/35R19?

255/35R19 is 0.11" taller and 80 mm narrower; the sidewall is -0.44". At an indicated 60 mph you'd actually be doing 60.3 mph.

Will 255/35R19 fit on 335/30R18 wheels?

No — 335/30R18 needs a 18" wheel and 255/35R19 a 19" wheel. This is a plus/minus-size swap that changes wheels too.