CarSpecsHQ

305/65R17 vs 285/75R16

285/75R16 is a safe swap for 305/65R17 by the usual ±3% rule: the diameter differs by +0.68%.

17" → 16"
305/65R17 32.61" · 285/75R16 32.83" · drawn to scale

Side by side

305/65R17285/75R16Difference
Overall diameter32.61"32.83"+0.22" (+0.68%)
Section width305 mm285 mm-20 mm
Sidewall7.81"8.42"+0.61"
Rim17"16"-1"
Circumference102.4"103.1"+0.7"
Revs per mile618614-4
Ride height——+0.11"
Speedometer reads 60 mph60.060.4+0.4 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.4 mph

With 285/75R16 on a car calibrated for 305/65R17, the speedometer reads 59.6 mph when you're really doing 60, and the odometer under-counts by 0.7%.

Speedo showsActual speed
30 mph30.2 mph
45 mph45.3 mph
60 mph60.4 mph
70 mph70.5 mph
80 mph80.5 mph

Other sizes close to 305/65R17

Questions

Can I replace 305/65R17 with 285/75R16?

285/75R16 is a safe swap for 305/65R17 by the usual ±3% rule: the diameter differs by +0.68%.

What's the difference between 305/65R17 and 285/75R16?

285/75R16 is 0.22" taller and 20 mm narrower; the sidewall is +0.61". At an indicated 60 mph you'd actually be doing 60.4 mph.

Will 285/75R16 fit on 305/65R17 wheels?

No — 305/65R17 needs a 17" wheel and 285/75R16 a 16" wheel. This is a plus/minus-size swap that changes wheels too.