CarSpecsHQ

235/75R17 vs 235/80R17

235/80R17 is a safe swap for 235/75R17 by the usual ±3% rule: the diameter differs by +3.00%.

17" rim
235/75R17 30.88" · 235/80R17 31.80" · drawn to scale

Side by side

235/75R17235/80R17Difference
Overall diameter30.88"31.80"+0.93" (+3.00%)
Section width235 mm235 mm0 mm
Sidewall6.94"7.40"+0.46"
Rim17"17"same
Circumference97.0"99.9"+2.9"
Revs per mile653634-19
Ride height——+0.46"
Speedometer reads 60 mph60.061.8+1.8 mph

Speedometer and odometer

020406080100120 reads 60 · actual 61.8 mph

With 235/80R17 on a car calibrated for 235/75R17, the speedometer reads 58.3 mph when you're really doing 60, and the odometer under-counts by 3.0%.

Speedo showsActual speed
30 mph30.9 mph
45 mph46.3 mph
60 mph61.8 mph
70 mph72.1 mph
80 mph82.4 mph

Other sizes close to 235/75R17

Questions

Can I replace 235/75R17 with 235/80R17?

235/80R17 is a safe swap for 235/75R17 by the usual ±3% rule: the diameter differs by +3.00%.

What's the difference between 235/75R17 and 235/80R17?

235/80R17 is 0.93" taller and 0 mm wider; the sidewall is +0.46". At an indicated 60 mph you'd actually be doing 61.8 mph.

Will 235/80R17 fit on 235/75R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 235 mm tire and the fender clearance.