CarSpecsHQ

245/50R16 vs 275/40R17

275/40R17 is a safe swap for 245/50R16 by the usual ±3% rule: the diameter differs by +0.06%.

16" → 17"
245/50R16 25.65" · 275/40R17 25.66" · drawn to scale

Side by side

245/50R16275/40R17Difference
Overall diameter25.65"25.66"+0.02" (+0.06%)
Section width245 mm275 mm+30 mm
Sidewall4.82"4.33"-0.49"
Rim16"17"+1"
Circumference80.6"80.6"+0.0"
Revs per mile786786-0
Ride height——+0.01"
Speedometer reads 60 mph60.060.0+0.0 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.0 mph

With 275/40R17 on a car calibrated for 245/50R16, the speedometer reads 60.0 mph when you're really doing 60, and the odometer under-counts by 0.1%.

Speedo showsActual speed
30 mph30.0 mph
45 mph45.0 mph
60 mph60.0 mph
70 mph70.0 mph
80 mph80.0 mph

Other sizes close to 245/50R16

Questions

Can I replace 245/50R16 with 275/40R17?

275/40R17 is a safe swap for 245/50R16 by the usual ±3% rule: the diameter differs by +0.06%.

What's the difference between 245/50R16 and 275/40R17?

275/40R17 is 0.02" taller and 30 mm wider; the sidewall is -0.49". At an indicated 60 mph you'd actually be doing 60.0 mph.

Will 275/40R17 fit on 245/50R16 wheels?

No — 245/50R16 needs a 16" wheel and 275/40R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.