275/40R21
Standard MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
Factory Spec Overview
The 275/40R21 tire size features an overall diameter of 29.66 inches, a section width of 10.8 inches (275mm), and rotates 680 times per mile. It is a standard factory tire fitment on 35+ vehicle models including Acura MDX.
Physical Dimensions & Specs
Overall Diameter
29.66"
753.4 mmSection Width
275 mm
10.83" wideSidewall Height
4.33"
110.0 mm (40% aspect)Revolutions / Mile
680
Circumference: 93.18"Rim Diameter
21"
Wheel sizeRecommended Rim Width
6.9" - 9.6"
Optimal rim width rangeSpeedometer & Alternate Size Calculator
Testing an alternate size for your vehicle? Compare 275/40R21 against any proposed tire size below:
Popular Comparisons:
Tire 1 (Stock / Base)275/40R21
Overall Height:29.7"
Sidewall:4.3"
Revs/Mile:680
Tire 2 (New / Compare)245/60R18
Overall Height:29.6"
Sidewall:5.8"
Revs/Mile:682
Visual Tire & Wheel Comparison
Speedometer Variance
-0.3%At 60 mph reading, actual speed is 59.8 mph
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 19.9 mph | -0.1 mph |
| 30 mph | 29.9 mph | -0.1 mph |
| 45 mph | 44.9 mph | -0.1 mph |
| 60 mph | 59.8 mph | -0.2 mph |
| 75 mph | 74.8 mph | -0.2 mph |
| 90 mph | 89.7 mph | -0.3 mph |
Fender & Suspension Clearance
Fitment Status: MODERATE RISK
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Inner Strut Space:7.7mm LESS clearance
Outer Fender Push:Extends 17.7mm further out
Ride Height Delta:-0.04" lower ground clearance
Vehicles That Fit 275/40R21 (35+ Models)
Factory standard and optional vehicle fitments utilizing 275/40R21 tires: