26.0" tall, 11.2" wide, 4.5" sidewall
A 285/40R17 tire is 26.0 inches (660 mm) tall and 11.2 inches wide. The sidewall is 40% of the width, 4.5 inches, on a 17-inch wheel, and the tire turns about 776 times per mile.
In flotation terms that is about 26.0x11.2R17. People often call it a 26-inch tire.
The size most often compared with it is 275/40R17, which is 0.3" shorter (−1.2%). At an indicated 60 mph you would be doing 59.3 mph on it.
| Current | New | Difference |
|---|
| Shows | Actual speed |
|---|
Same 17" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 285/40R17 | |
|---|---|---|---|---|---|
| 275/40R17 | 25.7" | 10.8" | 4.3" | −1.2% | compare |
| 295/40R17 | 26.3" | 11.6" | 4.6" | +1.2% | |
| 305/40R17 | 26.6" | 12.0" | 4.8" | +2.4% | |
| 285/45R17 | 27.1" | 11.2" | 5.0" | +4.3% | |
| 275/35R17 | 24.6" | 10.8" | 3.8" | −5.4% | |
| 265/50R17 | 27.4" | 10.4" | 5.2" | +5.6% | |
| 275/50R17 | 27.8" | 10.8" | 5.4" | +7.1% |
Sizes within 2% of 26.0" on 15" or 18" wheels.
| Size | Diameter | Width | Sidewall | vs 285/40R17 | |
|---|---|---|---|---|---|
| 215/65R15 | 26.0" | 8.5" | 5.5" | +0.1% | |
| 255/40R18 | 26.0" | 10.0" | 4.0" | +0.2% | |
| 255/55R15 | 26.0" | 10.0" | 5.5" | +0.3% | |
| 285/35R18 | 25.9" | 11.2" | 3.9" | −0.5% | |
| 235/60R15 | 26.1" | 9.3" | 5.6" | +0.5% | |
| 275/50R15 | 25.8" | 10.8" | 5.4" | −0.6% |
Actual speed when the speedometer is calibrated for 285/40R17.
| Speedometer shows | on 275/40R17 | on 295/40R17 | on 305/40R17 |
|---|---|---|---|
| 30 mph | 29.6 mph | 30.4 mph | 30.7 mph |
| 45 mph | 44.5 mph | 45.5 mph | 46.1 mph |
| 60 mph | 59.3 mph | 60.7 mph | 61.5 mph |
| 70 mph | 69.2 mph | 70.8 mph | 71.7 mph |
26.0 inches (660 mm). The sidewall is 4.5 inches.
11.2 inches (285 mm) section width, measured sidewall to sidewall.
About 26.0x11.2R17.
275/40R17 is −1.2% in diameter, within the common 3% guideline. It is 0.4" narrower.