305/70R16 vs 275/70R17
275/70R17 is 0.65 in (16.6 mm) shorter than 305/70R16, a −1.99% diameter difference. With the speedometer set for 305/70R16, an indicated 60 mph is 58.8 mph on 275/70R17.
Is this a safe swap?
Diameter difference −1.99%: within the ±3% guideline
By overall diameter alone, 275/70R17 falls inside the ±3% range commonly used as a guideline when replacing 305/70R16. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.
| Measurement | 305/70R16 | 275/70R17 | Difference | % diff |
|---|---|---|---|---|
| Overall diameter | 32.81 in (833.4 mm) | 32.16 in (816.8 mm) | −0.65 in (−16.6 mm) | −1.99% |
| Sidewall height | 8.41 in (213.5 mm) | 7.58 in (192.5 mm) | −0.83 in (−21.0 mm) | −9.84% |
| Section width | 12.01 in (305.0 mm) | 10.83 in (275.0 mm) | −1.18 in (−30.0 mm) | −9.84% |
| Circumference | 103.08 in (2,618.2 mm) | 101.03 in (2,566.1 mm) | −2.05 in (−52.2 mm) | −1.99% |
| Revolutions per mile | 615 | 627 | +12 | +2.03% |
| Indicated | Actual on 305/70R16 | Actual on 275/70R17 | Difference |
|---|---|---|---|
| 30 mph | 30.0 mph | 29.4 mph | −0.6 mph |
| 60 mph | 60.0 mph | 58.8 mph | −1.2 mph |
| 75 mph | 75.0 mph | 73.5 mph | −1.5 mph |
Ride-height change: 275/70R17 lowers the vehicle by 0.33 in (8.3 mm) at the axle (half the −16.6 mm diameter difference).
275/70R17 is 0.65 in shorter than 305/70R16 and 30 mm narrower, a 1.99% difference in overall diameter.
With the speedometer calibrated for 305/70R16, an indicated 60 mph is actually 58.8 mph on 275/70R17, and revolutions per mile change from 615 to 627.
275/70R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 305/70R16.
Size pages
Other comparisons with 305/70R16
- 32x11.50R15 vs 305/70R16
- 33x12.50R15 vs 305/70R16
- 305/70R16 vs 285/75R16
- 305/70R16 vs 33x12.50R16
- 305/70R16 vs 255/85R16
- 305/70R16 vs 305/65R17
- 305/70R16 vs 285/70R17
- 305/70R16 vs 33x12.50R17
Other comparisons with 275/70R17
- 32x11.50R15 vs 275/70R17
- 33x12.50R15 vs 275/70R17
- 265/75R16 vs 275/70R17
- 235/85R16 vs 275/70R17
- 285/75R16 vs 275/70R17
- 255/70R17 vs 275/70R17
- 275/65R17 vs 275/70R17
- 285/65R17 vs 275/70R17
Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.