285/40R20
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The 285/40R20 tire size features an overall diameter of 28.98 inches, a section width of 11.2 inches (285mm), and rotates 696 times per mile. It is a standard factory tire fitment on 87+ vehicle models including Alfa Romeo Stelvio.
Physical Dimensions & Specs
Overall Diameter
28.98"
736.1 mmSection Width
285 mm
11.22" wideSidewall Height
4.49"
114.0 mm (40% aspect)Revolutions / Mile
696
Circumference: 91.03"Rim Diameter
20"
Wheel sizeRecommended Rim Width
7.1" - 10"
Optimal rim width rangeWhere to Buy & Install 285/40R20 Tires
Looking for 285/40R20 tires? Skip hauling tires in your car—choose direct delivery to a local certified shop or doorstep delivery:
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Speedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare 285/40R20 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 20.4 mph | +0.4 mph |
| 30 mph | 30.6 mph | +0.6 mph |
| 45 mph | 45.9 mph | +0.9 mph |
| 60 mph | 61.2 mph | +1.2 mph |
| 75 mph | 76.5 mph | +1.5 mph |
| 90 mph | 91.9 mph | +1.9 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit 285/40R20 (87+ Models)
Factory standard and optional vehicle fitments utilizing 285/40R20 tires: