wearoneandahalf(1-1/2)timesaswellonthegovernmentcourseasatiregraded100.Therelativeperformanceoftiresdependsupontheactualconditionsoftheiruse,however,andmaydepartsignificantlyfromthenormduetovariationsindrivinghabits,servicepracticesanddifferencesinroadcharacteristicsandclimate.
TractionAA,A,B,C
Thetractiongrades,fromhighesttolowest,areAA,A,BandCandtheyrepresentthetire’sabilitytostoponwetpavementasmeasuredundercontrolledconditionsonspecifiedgovernmenttestsurfacesofasphaltandconcrete.AtiremarkedCmayhavepoortractionperformance.
Warning!
Thetractiongradeassignedtothisisbasedonbraking(straight-ahead)tractiontestsanddoesnotincludecornering(turned)traction,acceleration,hydroplaningorpeaktractioncharacteristics.
TemperatureA,B,C
ThetemperaturegradesareA(thehighest),BandC,representingthetire’sresistancetothegenerationofheatanditsabilitytodissipateheatwhentestedundercontrolledconditionsonaspecifiedindoorlaboratorytestwheel.Sustainedhightemperaturescancausethematerialof
thetiretodegenerateandreducetirelife,andexcessivetemperaturecanleadtosuddentirefailure.ThegradeCcorrespondstoalevelofperformancewhichallpassengercartiresmustmeetundertheFederalMotorVehicleSafetyStandardNo.109.GradesBandArepresenthigherlevelsofperformanceonthelaboratorytestwheelthantheminimumrequiredbylaw.
Warning!
Thetemperaturegradeforthistireisestab-lishedforatirethatisproperlyinflatedandnotoverloaded.Excessivespeed,underinfla-tion,orexcessiveloading,eitherseparatelyorincombination,cancauseheatbuildupandpossibletirefailure,resultinglossofcontrol,leadingtoseriouspersonalinjuryordeath.
Tirepressures
Warning!
Incorrecttirepressurecausesincreasedtirewearandadverselyaffectsroadhan-dling.Thiscouldleadtotirefailure,resultinginlossofcontrol,leadingtoseriouspersonalinjuryordeath.
Alwaysuseanaccuratetirepressuregaugewhencheckinginflationpressures.
Donotexceedthemaximumtirepressurelistedonthetiresidewall.
Pleaseobservethechapter”TIREPRESSUREPLATE”onpage240.
Coldtireinflationpressuremeans:alltiresmustbecold,ambienttemperaturemaximum(68°F/20°C),whenadjustingtheinflationpressure.Avoidsunlightstrikingthetiresbeforemeasuringcoldpressures,sincethepressureswouldrisefromtemperatureinfluence.
Valvecapsprotectthevalvefromdustanddirt,andthusfromleakage.Alwaysscrewcapstightlydown.Replacemissingcapsimmediately.
Useonlyplasticvalvecaps.
238PracticalTips,EmergencyService
Snowtires
Forabettergriponsnowandice,useradialM+Stireswithstuds.CheckwithyourlocalMotorVehicleBureauforpossiblerestrictions.
Danger!
Riskoflossofcontrolanddamagetothevehicleaswellasseriouspersonalinjuryordeath.Thestandardtiresproleandrubbermixtureareoptimizedforwetanddrydrivingconditions,andmaynotprovefavorableforsnowconditions.
ThereforeinstallM+Stiresbeforedrivinginsuchconditions.
Beforemountingsnowtires,consultwithyourPorschedealer.Hehasthetechnicalinformationnecessarytoadviseyouonwheelandtirecompatibility.
Snowtiresshouldhavethesameloadcapacityasoriginalequipmenttiresandshouldbemountedonallfourwheels.Snowtireswithstudsshouldberunatmoderatespeedswhennewinordertogivethestudstimetosettle.
Danger!
Tireswithbadlyworntreadsandstudsareverydangerousandcouldcauseaccidentsresultinginseriouspersonalinjuriesordeath.
Makesuretheyarereplacedimmediately.
Donotdriveavehicleequippedwithsnowtiresatprolongedhighspeed.Snowtiresdonothavethesamedegreeoftractionondry,wetorsnowfreeroadsasanormaltire.Furthermore,snowtireswearrapidlyundertheseconditions.
Complywithallstateandlocallawsgoverningsnowtireandtreaddepthrequirements.
Danger!
Riskofaccidentandseriouspersonalinjuryordeathduetoexcessivespeed.
Alwayscheckthemaximumspeedratingonthetiresidewallonanytireonthevehicle.
Neverexceedthemaximumspeedratingofthetires.
Fitwintertirestobothaxleswellbeforethecoldseasonbegins.YourauthorizedPorschedealerwillbepleasedtoadviseyou.
Maintenancenote
Werecommendfittingwintertiresonthevehicleattemperaturesbelow45°F(7°C).
Wintertireslosetheirtractioncapabilitywhentheirtreaddepthfallsbelow5/32in.(4mm).
244PracticalTips,EmergencyService
