275/70R16 vs 245/75R17

Q: Can I replace 275/70R16 with 245/75R17?

245/75R17 is a safe swap for 275/70R16 by the usual ±3% rule: the diameter differs by +1.00%.

245/75R17 is a safe swap for 275/70R16 by the usual ±3% rule: the diameter differs by +1.00%.

275/70R16 31.16" · 245/75R17 31.47" · drawn to scale

Side by side

	275/70R16	245/75R17	Difference
Overall diameter	31.16"	31.47"	+0.31" (+1.00%)
Section width	275 mm	245 mm	-30 mm
Sidewall	7.58"	7.23"	-0.34"
Rim	16"	17"	+1"
Circumference	97.9"	98.9"	+1.0"
Revs per mile	647	641	-6
Ride height	—	—	+0.16"
Speedometer reads 60 mph	60.0	60.6	+0.6 mph

Speedometer and odometer

With 245/75R17 on a car calibrated for 275/70R16, the speedometer reads 59.4 mph when you're really doing 60, and the odometer under-counts by 1.0%.

Speedo shows	Actual speed
30 mph	30.3 mph
45 mph	45.4 mph
60 mph	60.6 mph
70 mph	70.7 mph
80 mph	80.8 mph

Other sizes close to 275/70R16

Questions

Can I replace 275/70R16 with 245/75R17?

245/75R17 is a safe swap for 275/70R16 by the usual ±3% rule: the diameter differs by +1.00%.

What's the difference between 275/70R16 and 245/75R17?

245/75R17 is 0.31" taller and 30 mm narrower; the sidewall is -0.34". At an indicated 60 mph you'd actually be doing 60.6 mph.

Will 245/75R17 fit on 275/70R16 wheels?

No — 275/70R16 needs a 16" wheel and 245/75R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.