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P255/45R18

Passenger / P-Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The P255/45R18 tire size features an overall diameter of 27.04 inches, a section width of 10.0 inches (255mm), and rotates 746 times per mile. It is a standard factory tire fitment on 44+ vehicle models including Cadillac STS.

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Physical Dimensions & Specs

Overall Diameter

27.04"

686.8 mm

Section Width

255 mm

10.04" wide

Sidewall Height

4.52"

114.8 mm (45% aspect)

Revolutions / Mile

746

Circumference: 84.93"

Rim Diameter

18"

Wheel size

Recommended Rim Width

6.4" - 8.9"

Optimal rim width range

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Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare P255/45R18 against any proposed tire size below:

Popular Comparisons:
Tire 1 (Stock / Base)255/45R18
Overall Height:27.0"
Sidewall:4.5"
Revs/Mile:746
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

+9.4%At 60 mph reading, actual speed is 65.6 mph
IndicatedActual SpeedDiff
20 mph21.9 mph+1.9 mph
30 mph32.8 mph+2.8 mph
45 mph49.2 mph+4.2 mph
60 mph65.6 mph+5.6 mph
75 mph82.0 mph+7.0 mph
90 mph98.5 mph+8.5 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:+1.27" ground clearance

Vehicles That Fit P255/45R18 (44+ Models)

Factory standard and optional vehicle fitments utilizing P255/45R18 tires:

YearMake & ModelTrim / VariantLookup Specs
2005Cadillac STS4.6 A, AWDView 2005 STS ›
2005Cadillac STS4.6 A, RWDView 2005 STS ›
2006Cadillac STSBase, 4.6 A, AWDView 2006 STS ›
2006Cadillac STSBase, 4.6 A, RWDView 2006 STS ›
2006Cadillac STSVView 2006 STS ›
2007Cadillac STSBase, 4.6 A, AWDView 2007 STS ›
2007Cadillac STSBase, 4.6 A, RWDView 2007 STS ›
2007Cadillac STSVView 2007 STS ›
2008Cadillac STSBase, 3.6 V, AWDView 2008 STS ›
2008Cadillac STSBase, 3.6 V, RWDView 2008 STS ›
2008Cadillac STSBase, 4.6 A, AWDView 2008 STS ›
2008Cadillac STSBase, 4.6 A, RWDView 2008 STS ›
2008Cadillac STSVView 2008 STS ›
2009Cadillac STSBase, 3.6 V, AWDView 2009 STS ›
2009Cadillac STSBase, 4.6 A, AWDView 2009 STS ›
2009Cadillac STSBase, 3.6 V, RWDView 2009 STS ›
2009Cadillac STSBase, 4.6 A, RWDView 2009 STS ›
2009Cadillac STSVView 2009 STS ›
2010Cadillac STS3.6 V, RWDView 2010 STS ›
2010Cadillac STS4.6 A, AWDView 2010 STS ›
2010Cadillac STS4.6 A, RWDView 2010 STS ›
2011Cadillac STSRWDView 2011 STS ›
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 ›
2005Pontiac Grand PrixGXPView 2005 Grand Prix ›
2006Pontiac Grand PrixGXPView 2006 Grand Prix ›
2007Pontiac Grand PrixGXPView 2007 Grand Prix ›
2008Pontiac Grand PrixGXPView 2008 Grand Prix ›
2005Toyota TacomaX-RunnerView 2005 Tacoma ›
2006Toyota TacomaX-RunnerView 2006 Tacoma ›
2007Toyota TacomaX-RunnerView 2007 Tacoma ›
2008Toyota TacomaX-RunnerView 2008 Tacoma ›
2009Toyota TacomaX-RunnerView 2009 Tacoma ›
2010Toyota TacomaX-RunnerView 2010 Tacoma ›
2011Toyota TacomaX-RunnerView 2011 Tacoma ›
2012Toyota TacomaX-RunnerView 2012 Tacoma ›
2013Toyota TacomaX-RunnerView 2013 Tacoma ›