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255/40R18

Standard Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The 255/40R18 tire size features an overall diameter of 26.03 inches, a section width of 10.0 inches (255mm), and rotates 775 times per mile. It is a standard factory tire fitment on 150+ vehicle models including Audi RS 6, BMW M3.

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Physical Dimensions & Specs

Overall Diameter

26.03"

661.2 mm

Section Width

255 mm

10.04" wide

Sidewall Height

4.02"

102.1 mm (40% aspect)

Revolutions / Mile

775

Circumference: 81.78"

Rim Diameter

18"

Wheel size

Recommended Rim Width

6.4" - 8.9"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare 255/40R18 against any proposed tire size below:

Popular Comparisons:
Tire 1 (Stock / Base)255/40R18
Overall Height:26.0"
Sidewall:4.0"
Revs/Mile:775
Tire 2 (New / Compare)245/60R18
Overall Height:29.6"
Sidewall:5.8"
Revs/Mile:682

Visual Tire & Wheel Comparison

Tire 126.0" HeightTire 229.6" Height

Speedometer Variance

+13.6%At 60 mph reading, actual speed is 68.2 mph
IndicatedActual SpeedDiff
20 mph22.7 mph+2.7 mph
30 mph34.1 mph+4.1 mph
45 mph51.1 mph+6.1 mph
60 mph68.2 mph+8.2 mph
75 mph85.2 mph+10.2 mph
90 mph102.3 mph+12.3 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:+1.77" ground clearance

Vehicles That Fit 255/40R18 (150+ Models)

Factory standard and optional vehicle fitments utilizing 255/40R18 tires:

YearMake & ModelTrim / VariantLookup Specs
2003Audi RS 6RS 6View 2003 RS 6 ›
2001BMW M32D CoupeView 2001 M3 ›
2001BMW M32D ConvertibleView 2001 M3 ›
2002BMW M32D ConvertibleView 2002 M3 ›
2002BMW M32D CoupeView 2002 M3 ›
2003BMW M32D ConvertibleView 2003 M3 ›
2003BMW M32D CoupeView 2003 M3 ›
2004BMW M32D Convertible, S6View 2004 M3 ›
2004BMW M32D Convertible, S6S420GView 2004 M3 ›
2004BMW M32D Coupe, S6View 2004 M3 ›
2004BMW M32D Coupe, S6S420GView 2004 M3 ›
2005BMW M32D Convertible, S6View 2005 M3 ›
2005BMW M32D Convertible, S6S420GView 2005 M3 ›
2005BMW M32D Coupe, S6View 2005 M3 ›
2005BMW M32D Coupe, S6S420GView 2005 M3 ›
2006BMW M32D Coupe, S6S420G (SMG)View 2006 M3 ›
2006BMW M32D Convertible, S6S420G (SMG)View 2006 M3 ›
2006BMW M32D Convertible, S6S420GView 2006 M3 ›
2006BMW M32D Coupe, S6S420GView 2006 M3 ›
2007BMW M CoupeM CoupeView 2007 M Coupe ›
2007BMW M RoadsterM RoadsterView 2007 M Roadster ›
2008BMW M CoupeM CoupeView 2008 M Coupe ›
2008BMW M RoadsterM RoadsterView 2008 M Roadster ›
2012BMW 328i4D Sedan, Eng CD N20, Automatic TransView 2012 328i ›
2012BMW 328i4D Sedan, Eng CD N20, Standard TransView 2012 328i ›
2012BMW 328i4D Sedan, Eng CD N26View 2012 328i ›
2012BMW 335i4D Sedan, Automatic TransView 2012 335i ›
2012BMW 335i4D Sedan, Standard TransView 2012 335i ›
2013BMW 320iAutomatic TransView 2013 320i ›
2013BMW 320iStandard TransView 2013 320i ›
2013BMW 328i4D Sedan, Eng CD N20, Automatic TransView 2013 328i ›
2013BMW 328i4D Sedan, Eng CD N20, Standard TransView 2013 328i ›
2013BMW 328i4D Sedan, Eng CD N26View 2013 328i ›
2013BMW 328xi4D Sedan, Eng CD N20View 2013 328xi ›
2013BMW 328xi4D Sedan, Eng CD N26View 2013 328xi ›
2013BMW 335i4D Sedan, Automatic TransView 2013 335i ›
2013BMW 335i4D Sedan, Standard TransView 2013 335i ›
2013BMW 335xi4D Sedan, Automatic TransView 2013 335xi ›
2013BMW 335xi4D Sedan, Standard TransView 2013 335xi ›
2013BMW X128iView 2013 X1 ›
2013BMW X128isView 2013 X1 ›
2013BMW X135iView 2013 X1 ›
2013BMW 320xi320xiView 2013 320xi ›
2013BMW ActiveHybrid 3ActiveHybrid 3View 2013 ActiveHybrid 3 ›
2014BMW 328i xDrive4D Wagon, 2.0L Eng VIN CView 2014 328i xDrive ›
2014BMW 328i xDrive4D Wagon, 2.0L Eng, Eng CD N26View 2014 328i xDrive ›
2014BMW 328i xDrive4D Sedan, Eng CD N20B20AView 2014 328i xDrive ›
2014BMW 328i xDrive4D Wagon, 2.0L Eng, Eng CD N20B20AView 2014 328i xDrive ›
2014BMW 328i xDrive4D Sedan, Eng CD N26B20AView 2014 328i xDrive ›
2014BMW X1sDrive28iView 2014 X1 ›
2014BMW X1xDrive28iView 2014 X1 ›
2014BMW X1xDrive35iView 2014 X1 ›
2014BMW ActiveHybrid 3ActiveHybrid 3View 2014 ActiveHybrid 3 ›
2015BMW M3Automatic DCT TransView 2015 M3 ›
2015BMW M3Standard TransView 2015 M3 ›
2015BMW M42D ConvertibleView 2015 M4 ›
2015BMW M42D CoupeView 2015 M4 ›
2015BMW X1sDrive28iView 2015 X1 ›
2015BMW X1xDrive28iView 2015 X1 ›
2015BMW X1xDrive35iView 2015 X1 ›
2016BMW M3Automatic DCT TransView 2016 M3 ›
2016BMW M3Standard TransView 2016 M3 ›
2016BMW M4Base, 2D Convertible, Automatic DCT TransView 2016 M4 ›
2016BMW M4Base, 2D Convertible, Standard TransView 2016 M4 ›
2016BMW M4Base, 2D Coupe, Automatic DCT TransView 2016 M4 ›
2016BMW M4Base, 2D Coupe, Standard TransView 2016 M4 ›
2017BMW M3Automatic DCT TransView 2017 M3 ›
2017BMW M3Standard TransView 2017 M3 ›
2017BMW M42D Convertible, Automatic DCT TransView 2017 M4 ›
2017BMW M42D Convertible, Standard TransView 2017 M4 ›
2017BMW M42D Coupe, Automatic DCT TransView 2017 M4 ›
2017BMW M42D Coupe, Standard TransView 2017 M4 ›
2018BMW M3Standard TransView 2018 M3 ›
2018BMW M3Automatic DCT TransView 2018 M3 ›
2018BMW M42D Convertible, Automatic DCT TransView 2018 M4 ›
2018BMW M42D Convertible, Standard TransView 2018 M4 ›
2018BMW M42D Coupe, Automatic DCT TransView 2018 M4 ›
2018BMW M42D Coupe, Standard TransView 2018 M4 ›
2019BMW M4Base, 2D Convertible, Automatic DCT TransView 2019 M4 ›
2019BMW M4Base, 2D Convertible, Standard TransView 2019 M4 ›
2019BMW M4Base, 2D Coupe, Automatic DCT TransView 2019 M4 ›
2019BMW M4Base, 2D Coupe, Standard TransView 2019 M4 ›
2019BMW Z4Z4View 2019 Z4 ›
2020BMW M4Base, 2D Coupe, Standard TransView 2020 M4 ›
2020BMW M4Base, 2D Convertible, Standard TransView 2020 M4 ›
2020BMW M4Base, 2D Coupe, Automatic DCT TransView 2020 M4 ›
2020BMW M4Base, 2D Convertible, Automatic DCT TransView 2020 M4 ›
2020BMW Z4sDrive M40iView 2020 Z4 ›
2020BMW Z4sDrive30iView 2020 Z4 ›
2021BMW Z4sDrive M40iView 2021 Z4 ›
2021BMW Z4sDrive30iView 2021 Z4 ›
2022BMW Z4sDrive M40iView 2022 Z4 ›
2022BMW Z4sDrive30iView 2022 Z4 ›
2023BMW M440i xDrive2D CoupeView 2023 M440i xDrive ›
2023BMW M440i2D CoupeView 2023 M440i ›
2023BMW M440i2D ConvertibleView 2023 M440i ›
2023BMW Z4sDrive M40iView 2023 Z4 ›
2023BMW Z4sDrive30iView 2023 Z4 ›
2024BMW M440i xDrive2D CoupeView 2024 M440i xDrive ›
2024BMW M440i2D ConvertibleView 2024 M440i ›
2024BMW M440i2D CoupeView 2024 M440i ›
2024BMW Z4sDrive M40iView 2024 Z4 ›
2024BMW Z4sDrive30iView 2024 Z4 ›
2025BMW Z4sDrive M40i, Standard TransView 2025 Z4 ›
2025BMW Z4sDrive30iView 2025 Z4 ›
1998Jaguar XJRXJRView 1998 XJR ›
1999Jaguar XJRXJRView 1999 XJR ›
2000Jaguar XJRXJRView 2000 XJR ›
2001Jaguar XJRXJRView 2001 XJR ›
2002Jaguar XJ8BaseView 2002 XJ8 ›
2002Jaguar XJRBaseView 2002 XJR ›
2002Jaguar XJR100View 2002 XJR ›
2003Jaguar XJ8BaseView 2003 XJ8 ›
2003Jaguar XJRXJRView 2003 XJR ›
2014Lexus IS 350CF SportView 2014 IS 350C ›
2014Lexus IS 250CF SportView 2014 IS 250C ›
2015Lexus IS 250CF SportView 2015 IS 250C ›
2015Lexus IS 350CF SportView 2015 IS 350C ›
2003Mercedes-Benz SL500SL500View 2003 SL500 ›
2003Mercedes-Benz SL55SL55View 2003 SL55 ›
2004Mercedes-Benz SL500SL500View 2004 SL500 ›
2004Mercedes-Benz SL55SL55View 2004 SL55 ›
2004Mercedes-Benz SL600SL600View 2004 SL600 ›
2005Mercedes-Benz SL500SL500View 2005 SL500 ›
2005Mercedes-Benz SL55SL55View 2005 SL55 ›
2005Mercedes-Benz SL600SL600View 2005 SL600 ›
2006Mercedes-Benz CLS500CLS500View 2006 CLS500 ›
2006Mercedes-Benz SL500SL500View 2006 SL500 ›
2006Mercedes-Benz SL55SL55View 2006 SL55 ›
2006Mercedes-Benz SL600SL600View 2006 SL600 ›
2007Mercedes-Benz CLS550CLS550View 2007 CLS550 ›
2007Mercedes-Benz SL600SL600View 2007 SL600 ›
2007Mercedes-Benz SL550SL550View 2007 SL550 ›
2007Mercedes-Benz SL55SL55View 2007 SL55 ›
2008Mercedes-Benz CLS550CLS550View 2008 CLS550 ›
2008Mercedes-Benz SL550SL550View 2008 SL550 ›
2008Mercedes-Benz SL600SL600View 2008 SL600 ›
2009Mercedes-Benz CLS550CLS550View 2009 CLS550 ›
2009Mercedes-Benz SL550SL550View 2009 SL550 ›
2009Mercedes-Benz SL600SL600View 2009 SL600 ›
2010Mercedes-Benz CLS550CLS550View 2010 CLS550 ›
2010Mercedes-Benz E63E63View 2010 E63 ›
2011Mercedes-Benz CLS550CLS550View 2011 CLS550 ›
2011Mercedes-Benz E63E63View 2011 E63 ›
2011Mercedes-Benz SL550SL550View 2011 SL550 ›
2012Mercedes-Benz CLS550BaseView 2012 CLS550 ›
2012Mercedes-Benz CLS5504MaticView 2012 CLS550 ›
2012Mercedes-Benz SL550SL550View 2012 SL550 ›
2013Mercedes-Benz CLS550BaseView 2013 CLS550 ›
2013Mercedes-Benz CLS5504MaticView 2013 CLS550 ›