MG MG6 Series 2011 - Description

FrontSuspension
SuspensionSystem
Description
General
Thefrontsuspensioncomprises:
•T woMacPhersonstruts
•T wo'L'shapedlowerarms
•Anti-rollbar
•T woanti-rollbarlinks
•Frontsubframe
•Swivelhub,bearinganddriveange
Thefrontsuspensiondesignfeaturesanti-diveandanti-squat
geometryviatheanti-rollbarand1:1strutmovementratio.
Thelayoutanddesignofthestrutsminimizescamberlossdue
tosideforces,improvinghandlingandsteeringresponse.
FrontSubframe
Thesubframeisfabricatedfromhydro-formedtubingproviding
alightandstrongstructure.Allmachiningofcriticalgeometric
locationsisperformedafterfabricationtoensureaccurate
locationofthefrontsuspensionandsteeringcomponents.
Thesubframeismountedonsixrubbermountsandprovides
locationforallfrontsuspensioncomponents,exceptthestrut
topmounts,engineandgearboxmountings.Asubframe
brace,ttedbetweeneachsubframerearmountingpointand
thebody,providesadditionalrigiditytothissubframe.The
layoutofthemountingsensuresthatsubframemovement
undercorneringforces,whichcauseunwantedsteering
effects,isavoided.
MacPhersonStrut
T woMacPhersonstrutscontrolthedampingofthefront
suspension.Eachstrutassemblycomprisesadamperunit,
acoilspringandatopmountassembly.Thecoilspringis
retainedinacompressedconditionbetweenthestrutspring
seatandthetopmountassembly.Isolatorsateachendofthe
springreducenoisetransmittedfromthesuspensiontothe
body.Abearingisttedtotheundersideofthetopmount
assemblyandallowsthespringtorotateasthesteeringis
operated.Adustcoveristtedbetweenthebumpstop
andthedamperandprotectsthedamperrodfromdirtand
damage.
Thecoilspringaxisisoffsettotheaxisofthedamper.This
arrangementprovidessideloadcompensation,whichreduces
frictionwithinthedamper.
Damper
Thefrontdampersfeature85mmbumpand95mmrebound
damping.Eachdamperishanded.
Eachdamperisgaschargedandoillled,andisoftwin
tubeconstruction.Thetwintubeconstructionallowsthe
damperpistontooperateonaninnertubewithanoil/gas
cavitybetweentheinnerandoutertubes.Thisminimisesoil
cavitationandeliminatestheeffectofdamagetotheouter
tubeaffectingpistonoperation.
Thedamperisattachedatitslowerendtoalocationinthe
swivelhubandissecuredwithapinchbolt.Atangonthe
damperlocatesintheswivelhubandensuresthatthedamper
iscorrectlyorientated.
Thedamperrodislocatedinsteelinsertsinrubberbushes,
whichareintegralwiththetopmountingplate,andaresecured
withawasherandnut.Ahexagonisprovidedintheouterend
ofthedamperrodtorestraintherodfromrotatingwhenthe
nutistightened.Thedamperrodissealedinthedamperwith
alowfrictionseal.
Anangledspringseatisintegralwiththedamperbodyandalso
providestheattachmentpointfortheARBlink.
Aweldedbracket,nearthebottomofthedamper,allowsfor
theattachmentofthebrakehose,theABSspeedsensorcable
andontheRHdamper,thebrakepadwearsensorharness.
CoilSprings
Thecoilspringsttedtothestrutassemblyaremanufactured
fromsiliconchromevanadium.Thetopofthespringislocated
inaspringisolatorwhichinturnislocatedinthetopmount
bearing.Thebaseofthespring,whichisttedwithanisolator
sleeve,islocatedinaspringseatthatisintegralwiththe
damperbody.Bothisolatorsreducenoisetransmittedtothe
bodyfromthesuspension.Thefrontspringsdifferbetween
enginetypeandvehiclespecicationandeachspringcanbe
identiedbyacolourcodepaintedonthecoilsofthespring.
T opMountingPlateAssembly
Thetopmountingplateassemblycomprisesofthetop
mountingplate,adoublerubberbushandthreestuds.The
bushesarelocatedintothetopmountingplate.Steelinserts
arebondedintothecentreofthebushandpreventthe
locknutonthedamperrodovercompressingthebushwhen
itistightened.Theaxisofthebushisnotsquaretotheplate,
whichallowsthebearingtobelocatedwithitsaxisalignedto
theoffsetcoilspring.Threelugsontheundersideoftheplate
providefortheattachmentofthetopmountbearingwhichis
aninterferencetinthelugs.Thebearingandthebushare
notserviceableandanewtopmountingplateassemblymust
bettedifreplacementisrequired.
LowerArm
Thelowerarmisan'L'shaped,highstrengthalloyforgingthat
connectstheswivelhubtothesubframe.
Thearmhasanouterballjointthathasaparallelshank.The
parallelshanklocatesinasplitlocationinthebottomofthe
swivelhubandisclampedinpositionbyaboltandlocknut.
Aninnerballjointisalsottedandispositionedneartheroad
Version2.0551