255/85R16 vs 295/70R17

Q: Can I replace 255/85R16 with 295/70R17?

295/70R17 is a safe swap for 255/85R16 by the usual ±3% rule: the diameter differs by +0.58%.

295/70R17 is a safe swap for 255/85R16 by the usual ±3% rule: the diameter differs by +0.58%.

255/85R16 33.07" · 295/70R17 33.26" · drawn to scale

Side by side

	255/85R16	295/70R17	Difference
Overall diameter	33.07"	33.26"	+0.19" (+0.58%)
Section width	255 mm	295 mm	+40 mm
Sidewall	8.53"	8.13"	-0.40"
Rim	16"	17"	+1"
Circumference	103.9"	104.5"	+0.6"
Revs per mile	610	606	-4
Ride height	—	—	+0.10"
Speedometer reads 60 mph	60.0	60.4	+0.4 mph

Speedometer and odometer

With 295/70R17 on a car calibrated for 255/85R16, the speedometer reads 59.7 mph when you're really doing 60, and the odometer under-counts by 0.6%.

Speedo shows	Actual speed
30 mph	30.2 mph
45 mph	45.3 mph
60 mph	60.4 mph
70 mph	70.4 mph
80 mph	80.5 mph

Other sizes close to 255/85R16

Questions

Can I replace 255/85R16 with 295/70R17?

295/70R17 is a safe swap for 255/85R16 by the usual ±3% rule: the diameter differs by +0.58%.

What's the difference between 255/85R16 and 295/70R17?

295/70R17 is 0.19" taller and 40 mm wider; the sidewall is -0.40". At an indicated 60 mph you'd actually be doing 60.4 mph.

Will 295/70R17 fit on 255/85R16 wheels?

No — 255/85R16 needs a 16" wheel and 295/70R17 a 17" wheel. This is a plus/minus-size swap that changes wheels too.