275/60R20 vs 285/55R20
285/55R20 is 0.65 inches shorter than 275/60R20 and 10 mm (0.4 in) wider.
−2.0% height. Inside the usual 3% rule for a swap.
| Measurement | 275/60R20 | 285/55R20 | Difference |
|---|---|---|---|
| Overall height | 33.0 in | 32.3 in | −0.65 in (−2.0%) |
| Section width | 10.8 in | 11.2 in | +0.39 in (+10 mm) |
| Sidewall height | 6.5 in | 6.2 in | −0.32 in |
| Circumference | 103.6 in | 101.6 in | −2.0 in |
| Revolutions per mile | 611 | 624 | +12 |
| Ride height | −0.32 in |
Speedometer
With 285/55R20 fitted, a speedometer set up for 275/60R20 shows the first number when you are really doing the second.
- 3029.4 mph
- 4544.1 mph
- 6058.8 mph
- 7573.5 mph
The two sizes
275/60R20 is 33.0 inches tall with a 6.5-inch sidewall. 285/55R20 is 32.3 inches tall with a 6.2-inch sidewall. A taller sidewall rides softer and gives more ground clearance; a shorter one turns in more sharply. Try other pairs in the tire size calculator.
More comparisons
Questions
Which is bigger, 275/60R20 or 285/55R20?
275/60R20 is taller: 33.0 inches against 32.3. 285/55R20 is wider, at 285 mm.
Can I replace 275/60R20 with 285/55R20?
On height, yes: the difference is 2.0%, inside the usual 3% rule. Check that the extra width clears the suspension and suits your rim width.
How much does the speedometer change?
With 285/55R20 on a vehicle set up for 275/60R20, the speedometer shows 60 mph at a true 58.8 mph, and 70 at 68.6.