P285/40R18

Passenger / P-Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The P285/40R18 tire size features an overall diameter of 26.98 inches, a section width of 11.2 inches (285mm), and rotates 748 times per mile. It is a standard factory tire fitment on 9+ vehicle models including Ford Mustang.

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Physical Dimensions & Specs

Overall Diameter

26.98"

685.3 mm

Section Width

285 mm

11.22" wide

Sidewall Height

4.49"

114.0 mm (40% aspect)

Revolutions / Mile

748

Circumference: 84.75"

Rim Diameter

18"

Wheel size

Recommended Rim Width

7.1" - 10"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare P285/40R18 against any proposed tire size below:

Popular Comparisons:
Tire 1 (Stock / Base)285/40R18
Overall Height:27.0"
Sidewall:4.5"
Revs/Mile:748
Tire 2 (New / Compare)245/60R18
Overall Height:29.6"
Sidewall:5.8"
Revs/Mile:682

Visual Tire & Wheel Comparison

Tire 127.0" HeightTire 229.6" Height

Speedometer Variance

+9.6%At 60 mph reading, actual speed is 65.8 mph
IndicatedActual SpeedDiff
20 mph21.9 mph+1.9 mph
30 mph32.9 mph+2.9 mph
45 mph49.3 mph+4.3 mph
60 mph65.8 mph+5.8 mph
75 mph82.2 mph+7.2 mph
90 mph98.7 mph+8.7 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:+1.30" ground clearance

Vehicles That Fit P285/40R18 (9+ Models)

Factory standard and optional vehicle fitments utilizing P285/40R18 tires:

YearMake & ModelTrim / VariantLookup Specs
2007Ford MustangShelby GT500, 2D ConvertibleView 2007 Mustang
2007Ford MustangShelby GT500, 2D CoupeView 2007 Mustang
2008Ford MustangShelby GT500, 2D ConvertibleView 2008 Mustang
2008Ford MustangShelby GT500, 2D CoupeView 2008 Mustang
2008Ford MustangShelby GT500KRView 2008 Mustang
2009Ford MustangShelby GT500, 2D ConvertibleView 2009 Mustang
2009Ford MustangShelby GT500, 2D CoupeView 2009 Mustang
2009Ford MustangShelby GT500KRView 2009 Mustang
2010Ford MustangShelby GT500, 2D ConvertibleView 2010 Mustang