2012 Lexus LFA gearbox

36
Shifting
With regards to the drivetrain, the steering wheel-mounted paddle shift switches
command the automated dry single-plate clutch and rear-mounted ASG (Automated
Sequential Gearbox) transaxle. This fully automated configuration allows the driver to
upshift (+) or downshift (-) while keeping both hands on the steering wheel.
When the driver initiates a gear change using the paddle shift switches, the ASG
computer automatically controls and coordinates clutch engagement, engine speed,
torque transfer and gear select and shift operations.
The engine-mounted dr y single-plate clutch and rear-mounted transaxle are
connected via torque tube to provide the direct feel of a manual gearbox.
The ECU manages gear changes to provide intuitive response to the driver ’s
a c c e l e r a t i o n d e m a n d s . D o i n g s o a l l o w s g e a r c h a n g e s t o b e c a r r i e d o u t
instantaneously, providing a nearly uninterrupted flow of power. The engine speed
is computer controlled on upshifts and downshifts in order to ensure smooth clutch
engagement.
Naturally, shifting can be accomplished manually via the paddle shift switches.
However, shifting can also be performed automatically in AUTO mode. Switching to a
different driving mode using the driving mode selector switch or operating the paddle
shift switches will resume manual operation.
When in a manually shifted driving mode, the shift speeds may be tailored to the
driver’s preferences. Using the shift speed selector, the shift speed can be adjusted in
7 stages to a minimum shift time of approximately 0.15 seconds.

44
Steering
The driver’s steering inputs are conveyed by a large-diameter main shaft housed
within an aluminum alloy steering column, then through a joint made as straight as
possible onto the intermediate shaft. From here, inputs are mechanically transferred
to the wheels by an aluminum alloy monoblock steering gearbox. This efficient flow of
steering commands helps ensure a direct steering feel and precise wheel placement.
Joint Column assist type EPS
Aluminum alloy steering column
Intermediate shaft
Joint
Steering gearbox
The LFA’s power steering system features a column-assist type EPS (Electric Power
Steering) system. This computer-controlled system takes into account factors such
as vehicle speed, steering effort and steering rate in order to provide linear steering
feedback. Furthermore, the teeth of the reduction gear, a section of the motor
responsible for sending large amounts of torque to the main shaft, have been coated
with power grease to reduce torque fluctuations and provide smoother steering feel.

46
■
■Steering rack and gearbox
The steering gearbox consists of a monoblock aluminum alloy rack and pinion unit
mounted to the front suspension member using four rigid mounts. This allows the
driver to feel as if they are solidly connected to the road. An overall steering ratio of
14.3:1 allows the driver to precisely follow their intended line through a corner.
S107-06The joint between the steering shaft and gearbox is set at a narrow angle (approx. 10˚)
for a highly efficient connection that allows even subtle steering inputs to be accurately
conveyed, keeping the LFA directly on the driver’s intended path no matter what the
situation, whether it be a winding road or an extremely fast straightaway. Joint angle: Approx. 10˚

111
Technical information
Clutch and Transaxle
ClutchTypeDry Single-Plate Clutch
Diaphragm Spring
Operation Hydraulic Cylinder
Clutch Cover TypeDiaphragm Spring Turnover
Clutch Disc Diameter 240 mm
Transaxle Type ASG
(Automated Sequential Gearbox)
Transaxle Model RB60M
Front Counter Gear Ratio* 1.259
Transaxle Gear Ratios 1st3.231
2nd 2.188
3rd 1.609
4th 1.233
5th 0.970
6th 0.795
Rev 3.587
Differential Gear Ratio 3.417
Differential Type TORSEN
® LSD
Rear Transaxle Gear Oil Oil Viscosity“LT 75W-85” API GL-5
Rear Transaxle Gear Oil Capacity 5.3 L (5.6 qt., 4.7 Imp. qt.)
*: The front counter gear is lubricated by engine oil.

118
NNeedle 67
Negative battery terminal
structure 99
NORMAL mode 58
NORMAL mode
(control characteristics) 26
NORMAL mode (selection) 27
OOil change interval 67
Oil inspection 67
Oil level 67, 68
Oil level gauge 68, 69
Oil level sensor 68
Oil Maintenance 67
Oil pressure sensor 62
Oil replacement 67
Oil tank 68
Oil temperature sensor 61
Operating the driving mode
selector switch 26
Optimum driving position 20
Outer rear view mirror switches 9
Outside rear view mirror switches 9
Overall gear ratio 46
Over-rev 70
PPaddle shift switches 40, 4 1
Paddle shifters 40, 41
Parasitic current (dark current) 93
Parking 11
Parking brake 9, 52
Parking brake (vehicle long-term
storage) 92
Parking brake calipers 52
Parking brake switch 9
Partition glass care 87
Partition glass cleaning 87
Partition glass maintenance 87
Peak-hold 67
Pedal anti-slip pattern 51
Pedal texture 51
Petrol 63
Petrol filler door 12
Petrol level units selection 67
Petrol tank 63
Petrol tank cap 12
Petrol tank volume 12
Petrol type 12
Polycarbonate resin glass
maintenance 87
Powertrain 56
Propeller shaft 38
RRack and pinion gearbox 46
Rear brake caliper 52
Rear brake rotor 53
Rear disc 53
Rear hatch 12
Rear hatch access 95
Rear hatch manual unlock 95
Rear quarter window care 80

120
Speed Indicator 67
Speedometer 57, 67
SPORT mode 58
SPORT mode
(control characteristics) 26
SPORT mode (selection) 27
Starting off 11
Starting the engine 9, 1 0
Starting the engine by connecting
an external battery 98
Status 67
Steering 44
Steering adjustment 23
Steering column adjustment 9
Steering column shaft-mounted
EPS (Electric Power Steering)
system 44
Steering rack and gearbox 46
Steering system 44
Steering wheel adjustment 23
Steering wheel adjustment lever 9
Steering wheel adjustment
range 23, 45
Steering wheel position
adjustment 23
Steering wheel shape 45
Steering wheel telescoping range 23
Steering wheel tilt range 23
Stop and go traffic 37
Stopwatch 67 , 72
Suppressing dark current
(parasitic current) 93
Suspension adjustment 47
Suspension geometry 47
Synchronizer rings 39
Synchronizers 39
Synchros 39
TTachometer 59
Telescopic adjustment range 23
Telltale needle 71
Temperature display units
selection 67
TFT LCD panel 56
Throttle body valve opening
angle 33
Throttle response 33, 56
Throttle response adjustment 33
Throttle valve opening angle 33
Tilt and telescopic steering control
lever 9
Tilt range 23
Tilt sensor deactivation 102
Tires (vehicle long-term storage) 92
Tool bag 100
Topping up the oil level 69
Torque tube 38
TORSEN® LSD 39
Tow hook 100
Tow truck selection 100
Towing eyelet 100