P315/40R18
Passenger / P-MetricFactory Specs, Physical Dimensions & Compatible Vehicle Applications
The P315/40R18 tire size features an overall diameter of 27.92 inches, a section width of 12.4 inches (315mm), and rotates 722 times per mile. It is a standard factory tire fitment on 6+ vehicle models including Dodge Challenger.
Physical Dimensions & Specs
Overall Diameter
27.92"
709.2 mmSection Width
315 mm
12.40" wideSidewall Height
4.96"
126.0 mm (40% aspect)Revolutions / Mile
722
Circumference: 87.72"Rim Diameter
18"
Wheel sizeRecommended Rim Width
7.9" - 11"
Optimal rim width rangeWhere to Buy & Install P315/40R18 Tires
Looking for P315/40R18 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 P315/40R18 against any proposed tire size below:
Visual Tire & Wheel Comparison
Speedometer Variance
| Indicated | Actual Speed | Diff |
|---|---|---|
| 20 mph | 21.2 mph | +1.2 mph |
| 30 mph | 31.8 mph | +1.8 mph |
| 45 mph | 47.7 mph | +2.7 mph |
| 60 mph | 63.6 mph | +3.6 mph |
| 75 mph | 79.4 mph | +4.4 mph |
| 90 mph | 95.3 mph | +5.3 mph |
Fender & Suspension Clearance
Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.
Vehicles That Fit P315/40R18 (6+ Models)
Factory standard and optional vehicle fitments utilizing P315/40R18 tires: