TireSizeCheck

265/70R17 vs 275/65R17

Fitment assessment

Fitment not determined

Diameter change

−1.7%

Overall diameter changes 1.7%; section width changes 10 mm. Diameter comparison alone cannot confirm fitment. Verify the vehicle maker's approved rim width, tire load and speed ratings, and clearance at full steering lock and suspension compression. Confirm any possible ABS, traction-control, speedometer, and drivetrain effects with the vehicle maker or a qualified tire professional.

New overall diameter

31.07″

was 31.61″

True speed at an indicated 60

59.0 mph

your speedo reads high

Revolutions per mile

649

was 638, +11

Measurement 265/70R17 275/65R17 Change
Overall diameter 31.61″ 31.07″ −0.53″ (−1.7%)
Sidewall height 7.30″ (185.5 mm) 7.04″ (178.8 mm) −6.8 mm
Tread width 265 mm 275 mm +10 mm
Circumference 99.29″ 97.62″ −1.67″
Revs per mile 638 649 +11
Speedometer error baseline −1.7% reads high

Diameter overlay

265/70R17 275/65R17

Speedometer check

With 275/65R17 fitted, when the speedometer shows the indicated speed, your actual speed is:

25 mph shown

24.6 mph actual

35 mph shown

34.4 mph actual

45 mph shown

44.2 mph actual

55 mph shown

54.1 mph actual

65 mph shown

63.9 mph actual

75 mph shown

73.7 mph actual

Common questions

Will 275/65R17 fit instead of 265/70R17?
Overall diameter changes 1.7%; section width changes 10 mm. Diameter comparison alone cannot confirm fitment. Verify the vehicle maker's approved rim width, tire load and speed ratings, and clearance at full steering lock and suspension compression. Confirm any possible ABS, traction-control, speedometer, and drivetrain effects with the vehicle maker or a qualified tire professional. Overall diameter goes from 31.61″ to 31.07″, a change of −1.7%. The rule of thumb most shops use: under 3% is fine, 3 to 5% needs a clearance check, over 5% needs recalibration.
How far off will my speedometer read on 275/65R17?
At an indicated 60 mph you are really doing about 59.0 mph, a −1.7% error. The speedometer reads high, so you are going slower than it shows.
What is the difference in revolutions per mile between 265/70R17 and 275/65R17?
265/70R17 turns about 638 times per mile and 275/65R17 turns about 649, a difference of +11. Your speedometer and odometer both count rotations, so this number is what throws them off.