CarSpecsHQ

245/75R17 vs 235/85R16

235/85R16 is a safe swap for 245/75R17 by the usual ±3% rule: the diameter differs by +0.83%.

17" → 16"
245/75R17 31.47" · 235/85R16 31.73" · drawn to scale

Side by side

245/75R17235/85R16Difference
Overall diameter31.47"31.73"+0.26" (+0.83%)
Section width245 mm235 mm-10 mm
Sidewall7.23"7.86"+0.63"
Rim17"16"-1"
Circumference98.9"99.7"+0.8"
Revs per mile641636-5
Ride height——+0.13"
Speedometer reads 60 mph60.060.5+0.5 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.5 mph

With 235/85R16 on a car calibrated for 245/75R17, the speedometer reads 59.5 mph when you're really doing 60, and the odometer under-counts by 0.8%.

Speedo showsActual speed
30 mph30.2 mph
45 mph45.4 mph
60 mph60.5 mph
70 mph70.6 mph
80 mph80.7 mph

Other sizes close to 245/75R17

Questions

Can I replace 245/75R17 with 235/85R16?

235/85R16 is a safe swap for 245/75R17 by the usual ±3% rule: the diameter differs by +0.83%.

What's the difference between 245/75R17 and 235/85R16?

235/85R16 is 0.26" taller and 10 mm narrower; the sidewall is +0.63". At an indicated 60 mph you'd actually be doing 60.5 mph.

Will 235/85R16 fit on 245/75R17 wheels?

No — 245/75R17 needs a 17" wheel and 235/85R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.