315/30R20

Standard Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The 315/30R20 tire size features an overall diameter of 27.44 inches, a section width of 12.4 inches (315mm), and rotates 735 times per mile. It is a standard factory tire fitment on 3+ vehicle models including Ford Mustang.

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Physical Dimensions & Specs

Overall Diameter

27.44"

697.0 mm

Section Width

315 mm

12.40" wide

Sidewall Height

3.72"

94.5 mm (30% aspect)

Revolutions / Mile

735

Circumference: 86.21"

Rim Diameter

20"

Wheel size

Recommended Rim Width

7.9" - 11"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare 315/30R20 against any proposed tire size below:

Popular Comparisons:
Tire 1 (Stock / Base)315/30R20
Overall Height:27.4"
Sidewall:3.7"
Revs/Mile:735
Tire 2 (New / Compare)245/60R18
Overall Height:29.6"
Sidewall:5.8"
Revs/Mile:682

Visual Tire & Wheel Comparison

Tire 127.4" HeightTire 229.6" Height

Speedometer Variance

+7.8%At 60 mph reading, actual speed is 64.7 mph
IndicatedActual SpeedDiff
20 mph21.6 mph+1.6 mph
30 mph32.3 mph+2.3 mph
45 mph48.5 mph+3.5 mph
60 mph64.7 mph+4.7 mph
75 mph80.8 mph+5.8 mph
90 mph97.0 mph+7.0 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:+1.07" ground clearance

Vehicles That Fit 315/30R20 (3+ Models)

Factory standard and optional vehicle fitments utilizing 315/30R20 tires:

YearMake & ModelTrim / VariantLookup Specs
2020Ford MustangShelby GT500View 2020 Mustang
2021Ford MustangShelby GT500View 2021 Mustang
2022Ford MustangShelby GT500View 2022 Mustang