265/70R17 vs 255/75R17

Q: Can I replace 265/70R17 with 255/75R17?

255/75R17 is a safe swap for 265/70R17 by the usual ±3% rule: the diameter differs by +1.43%.

255/75R17 is a safe swap for 265/70R17 by the usual ±3% rule: the diameter differs by +1.43%.

265/70R17 31.61" · 255/75R17 32.06" · drawn to scale

Side by side

	265/70R17	255/75R17	Difference
Overall diameter	31.61"	32.06"	+0.45" (+1.43%)
Section width	265 mm	255 mm	-10 mm
Sidewall	7.30"	7.53"	+0.23"
Rim	17"	17"	same
Circumference	99.3"	100.7"	+1.4"
Revs per mile	638	629	-9
Ride height	—	—	+0.23"
Speedometer reads 60 mph	60.0	60.9	+0.9 mph

Speedometer and odometer

With 255/75R17 on a car calibrated for 265/70R17, the speedometer reads 59.2 mph when you're really doing 60, and the odometer under-counts by 1.4%.

Speedo shows	Actual speed
30 mph	30.4 mph
45 mph	45.6 mph
60 mph	60.9 mph
70 mph	71.0 mph
80 mph	81.1 mph

Other sizes close to 265/70R17

Questions

Can I replace 265/70R17 with 255/75R17?

255/75R17 is a safe swap for 265/70R17 by the usual ±3% rule: the diameter differs by +1.43%.

What's the difference between 265/70R17 and 255/75R17?

255/75R17 is 0.45" taller and 10 mm narrower; the sidewall is +0.23". At an indicated 60 mph you'd actually be doing 60.9 mph.

Will 255/75R17 fit on 265/70R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 255 mm tire and the fender clearance.