265/75R16 vs 275/70R17
New overall diameter
32.16″
was 31.65″
True speed at an indicated 60
61.0 mph
speedometer reads low
Revolutions per mile
627
was 637 · −10
Switching from 265/75R16 to 275/70R17? Everything that changes is below — sidewall, tread width, circumference, revolutions per mile and speedometer error at road speeds.
| Measurement | 265/75R16 | 275/70R17 | Change |
|---|---|---|---|
| Overall diameter | 31.65″ | 32.16″ | +0.51″ (+1.6%) |
| Sidewall height | 7.82″ (198.8 mm) | 7.58″ (192.5 mm) | −6.3 mm |
| Tread width | 265 mm | 275 mm | +10 mm |
| Circumference | 99.43″ | 101.03″ | +1.60″ |
| Revs per mile | 637 | 627 | −10 |
| Speedometer error | baseline | +1.6% | reads low |
Diameter overlay
265/75R16 275/70R17
Speedometer check
With 275/70R17 fitted, when the speedometer shows the indicated speed, your actual speed is:
25 mph shown
25.4 mph actual
35 mph shown
35.6 mph actual
45 mph shown
45.7 mph actual
55 mph shown
55.9 mph actual
65 mph shown
66.0 mph actual
75 mph shown
76.2 mph actual
Common questions
- Will 275/70R17 fit instead of 265/75R16?
- Good fit. Within the 3% rule — overall diameter changes only 1.6%. Speedometer calibration, ABS, traction control and gearing all stay in their intended range. Your speedometer will read lower than your true speed. Overall diameter goes from 31.65″ to 32.16″, a change of +1.6%. As a rule of thumb, under 3% is safe, 3–5% needs a clearance check, and over 5% is not recommended.
- How far off will my speedometer read on 275/70R17?
- At an indicated 60 mph you would actually be travelling about 61.0 mph — a +1.6% error. The speedometer reads low, so you are going faster than it shows.
- What is the difference in revolutions per mile between 265/75R16 and 275/70R17?
- 265/75R16 turns roughly 637 revolutions per mile; 275/70R17 turns roughly 627. That is a change of −10 revolutions per mile, which is what shifts odometer and speedometer readings.