235/55R18 vs 295/35R20
295/35R20 is 0.05 in (1.2 mm) shorter than 235/55R18, a −0.17% diameter difference. With the speedometer set for 235/55R18, an indicated 60 mph is 59.9 mph on 295/35R20.
Is this a safe swap?
Diameter difference −0.17%: under 1%
By overall diameter alone, 295/35R20 is a near match for 235/55R18; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.
| Measurement | 235/55R18 | 295/35R20 | Difference | % diff |
|---|---|---|---|---|
| Overall diameter | 28.18 in (715.7 mm) | 28.13 in (714.5 mm) | −0.05 in (−1.2 mm) | −0.17% |
| Sidewall height | 5.09 in (129.3 mm) | 4.06 in (103.3 mm) | −1.02 in (−26.0 mm) | −20.12% |
| Section width | 9.25 in (235.0 mm) | 11.61 in (295.0 mm) | +2.36 in (+60.0 mm) | +25.53% |
| Circumference | 88.52 in (2,248.4 mm) | 88.37 in (2,244.7 mm) | −0.15 in (−3.8 mm) | −0.17% |
| Revolutions per mile | 716 | 717 | +1 | +0.17% |
| Indicated | Actual on 235/55R18 | Actual on 295/35R20 | Difference |
|---|---|---|---|
| 30 mph | 30.0 mph | 29.9 mph | −0.1 mph |
| 60 mph | 60.0 mph | 59.9 mph | −0.1 mph |
| 75 mph | 75.0 mph | 74.9 mph | −0.1 mph |
Ride-height change: 295/35R20 lowers the vehicle by 0.02 in (0.6 mm) at the axle (half the −1.2 mm diameter difference).
295/35R20 is 0.05 in shorter than 235/55R18 and 60 mm wider, a 0.17% difference in overall diameter.
With the speedometer calibrated for 235/55R18, an indicated 60 mph is actually 59.9 mph on 295/35R20, and revolutions per mile change from 716 to 717.
295/35R20 mounts on a 20-inch wheel, a plus-2 fitment from the 18-inch wheel of 235/55R18.
Size pages
Other comparisons with 235/55R18
- 235/65R16 vs 235/55R18
- 205/75R16 vs 235/55R18
- 225/70R16 vs 235/55R18
- 245/65R16 vs 235/55R18
- 215/65R17 vs 235/55R18
- 235/60R17 vs 235/55R18
- 235/50R18 vs 235/55R18
- 215/55R18 vs 235/55R18
Other comparisons with 295/35R20
- 255/50R18 vs 295/35R20
- 285/45R18 vs 295/35R20
- 285/40R19 vs 295/35R20
- 255/45R19 vs 295/35R20
- 235/50R19 vs 295/35R20
- 295/40R19 vs 295/35R20
- 295/30R20 vs 295/35R20
- 275/35R20 vs 295/35R20
Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.