255/60R15 vs 275/60R15

275/60R15 is 0.9" taller than 255/60R15 (3.5%)

Diameter difference+3.49%diameter 27.05" → 27.99"
255/60R15275/60R15
255/60R15275/60R15Difference
Overall diameter27.05"27.99"+0.94"
Section width10.04"10.83"+0.79"
Sidewall height6.02"6.50"+0.47"
Circumference85.0"87.9"+3.0"
Revolutions per mile746720−25
Wheel diameter15"15"±0"

Speedometer

ShowsActualDiff
30 mph31.0 mph+1.0
45 mph46.6 mph+1.6
60 mph62.1 mph+2.1
70 mph72.4 mph+2.4
80 mph82.8 mph+2.8

Gear ratio to match

CurrentEquivalent
3.423.54
3.553.67
3.733.86
4.104.24

275/60R15 is 0.94" taller than 255/60R15, a +3.49% change in diameter. That is more than the 3% many tire shops use as a limit, so plan on recalibrating the speedometer and checking ABS and stability control.

Ground clearance changes by 0.47" (half the diameter change), and the tire needs 0.47" more room above it.

275/60R15 is 0.79" wider. On the same wheel offset about half of that, 0.39", moves toward the suspension and half toward the fender.

Both fit a 15" wheel; the sidewall is 0.47" taller on 275/60R15.

Details: 255/60R15 in inches · 275/60R15 in inches · change sizes in the calculator

FAQ

What is the difference between 255/60R15 and 275/60R15?

275/60R15 is 0.94" taller (+3.49%) and 0.79" wider than 255/60R15.

Will 275/60R15 change my speedometer?

Yes, by +3.49%. When the speedometer shows 60 mph you would be going 62.1 mph.

Can I replace 255/60R15 with 275/60R15?

It is a +3.5% diameter change, larger than the common 3% guideline, so check clearance and plan to recalibrate.