Allison Transmission 3500 User Manual

10.0TRANSMISSIONCOMPONENTS
10.1TORQUECONVERTER
Thetorqueconvertermultipliesenginetorqueandtransferssmooth,
uninterruptedpowertothewheelsquickly.Thetorqueconverterconsistsof
thesefourcomponents:
•Pump–inputelementdrivendirectlybytheengine
•Turbine–outputelementhydraulicallydrivenbythepump
•Stator–reaction(torquemultiplying)element
•LockupClutch–mechanicallycouplesthepumpandturbinewhen
commandedbytheTransmissionControlModule(TCM).
Whenthepumpturnsfasterthantheturbineandthestatorisstationary,the
torqueconverterismultiplyingtorque.Whentheturbineapproachesthe
speedofthepump,thestatorstartstorotatewiththepumpandturbine.When
thisoccurs,torquemultiplicationstopsandthetorqueconverterfunctionsasa
uidcoupling.Thelockupclutchislocatedinsidethetorqueconverterand
consistsofthefollowingcomponents:
•Pistonandbackplate–drivenbytheengine
•Clutchplate/damper(locatedbetweenthepistonandthe
backplate)–splinedtotheconverterturbine
Thelockupclutch/torsionaldamperisengagedandreleasedinresponseto
electronicsignalsfromtheTCM.Lockupclutchengagementprovidesadirect
drivefromtheenginetothetransmissioninput.Thiseliminatesconverter
slippageandmaximizesfueleconomyandvehiclespeed.Thelockupclutch
releasesatlowerspeedsorwhentheTCMdetectsconditionsrequiringitto
bereleased.
Thetorsionaldampertriestoabsorbenginetorsionalvibrationinanattempt
topreventtransmittingenginetorsionalvibrationonthroughtotransmission
components(clutches,etc),oritemsboltedtothetransmission.
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Allison Transmission 3500 Specifications

General

Retarder	Optional
Protection Rating	IP67
Gears	6-speed
Type	Automatic
Input Voltage	12V or 24V
Communication Protocol	J1939
Operating Temperature Range	-40°C to +85°C