BMW F97 Technical Training Manual page 25

F97/F98￿Complete￿Vehicle
4.￿Powertrain
With￿the￿M8HP76￿M￿Sport￿Steptronic￿transmission,￿which￿is￿based￿on￿the￿BMW￿AG￿8HPTU2￿gearbox,
customers￿benefit￿from￿significantly￿improved￿gear￿shift￿responsiveness￿and￿even￿further￿optimized
control￿of￿the￿converter￿lock-up￿clutch.
This￿has￿been￿made￿possible￿by￿the￿further￿development￿of￿converter￿technology￿to￿effectively￿damp
rotational￿irregularities￿in￿the￿drivetrain￿with￿a￿turbine￿torsional￿vibration￿damper.￿As￿a￿result,￿the
operating￿ranges￿in￿which￿the￿converter￿lock-up￿clutch￿has￿to￿be￿controlled￿are￿reduced￿even￿further
because￿the￿converter￿lock-up￿clutch￿is￿fully￿engaged￿in￿the￿vast￿majority￿of￿driving￿situations.￿This
provides￿for￿an￿even￿more￿direct￿connection￿of￿the￿M8HP76￿transmission￿to￿the￿complete￿drivetrain,
resulting￿in￿an￿even￿sportier￿driving￿experience￿and￿reduced￿fuel￿consumption.
The￿power￿transmission￿capacity￿of￿the￿torque￿converter￿has￿been￿adapted￿to￿the￿S58B30T0￿engine.
In￿the￿F97/F98￿the￿"Idle￿coasting"￿function￿known￿from￿the￿BMW￿AG￿vehicles￿is￿not￿implemented.
However,￿the￿M8HP76￿supports,￿as￿known￿from￿the￿BMW￿AG￿vehicles,￿the￿"ConnectedShift"
function.
Transmission￿ratios￿–￿F97/F98
Transmission￿designation
Transmission￿ratio￿spread
Maximum￿engine￿speed￿[rpm]
Torque￿[Nm]
Ratio￿[:1]￿1st￿gear
Ratio￿[:1]￿2nd￿gear
Ratio￿[:1]￿3rd￿gear
Ratio￿[:1]￿4th￿gear
Ratio￿[:1]￿5th￿gear
Ratio￿[:1]￿6th￿gear
Ratio￿[:1]￿7th￿gear
Ratio￿[:1]￿8th￿gear
Ratio￿[:1]￿reverse￿gear
4.2.2.￿Transmission￿oil￿cooling
The￿plastic￿transmission￿sump￿has￿been￿replaced￿by￿an￿aluminum￿version￿with￿larger￿cooling￿fins￿and
the￿opening￿point￿of￿the￿transmission￿oil￿thermostat￿lowered,￿thereby￿improving￿the￿cooling￿of￿the
M8HP76￿transmission.
A￿transmission￿oil￿cooler￿with￿a￿thermostat￿is￿used￿to￿cool￿the￿M8HP76￿on￿the￿F97/F98.￿This
additional￿transmission￿oil￿cooler,￿which￿is￿designed￿as￿a￿plate￿heat￿exchanger,￿operates￿according￿to
the￿oil-to-air￿heat￿exchanger￿principle￿and￿is￿installed￿vertically￿in￿front￿of￿the￿radiator￿assembly.
F97/F98
M8HP76￿(ZF)
7.8
7200
650
5.000
3.200
2.143
1.720
1.313
1.000
0.823
0.640
3.478
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