Introduction
Manual Transmission AJ-V6/AJ28
64In Europeon markets only, manual transmission is fitted as standard on the V6 entry S-TYPE model and
as an option on the V6 high specification model. Manual transmission is not available for the V8 variant.
The manual transmission is a 5 speed Getrag 221 unit with the following features:
¥ direct gearing (1:1) on 5th gear (it is normally on 4th) reduces losses
¥ twin synchronising cones on 1st and 2nd gears provide a smoother change
¥ four plane shift gate (R-1-3-5) with Ôknock-overÕ protection on the Reverse position.
A reverse light switch and speed sensor are fitted on the LH side of the gearbox. The speed sensor
monitors output shaft speed to provide an input to the PCM in addition to the signals received from the
road wheel speed sensors.
Specification:
Gear ratios: 1st 2nd 3rd 4th 5th Reverse
4.23 : 1 2.52 : 1 1.67 : 1 1.22 : 1 1 : 1 4.14 : 1
Weight: 33 kg (72 lbs)
Oil specification: ESSOD21065
Oil change interval: 60,000 miles (96,000 km)
D.307.312
MANUAL TRANSMISSION, CLUTCH ASSEMBLY AND DUAL MASS FLYWHEEL
D.307.312
Reverse Light Switch
Speed Sensor
Manual Transmission AJ-V6/AJ28
66With a conventional clutch, increased lining wear
causes the angle of the actuating diaphragm
spring to change as the pressure plate moves
axially towards the engine, requiring a greater
force to operate the clutch (diaphragm actuating
force varies with diaphragm angle). The self
adjusting clutch eliminates the problem by
allowing the diaphragm spring to follow the axial
movement of the pressure plate thus maintaining
the diaphragm spring at the same angle
throughout the life of the clutch. As well as
maintaining a constant pedal pressure, the clamp
force on the pressure plate also remains constant
with wear.
The operation is shown in the diagram. The
diaphragm spring is not fixed at its rotation point
like the conventional system but pivots between a
sensor spring and an adjuster ring. The sensor
spring provides a counter force which is just
sufficient to retain the diaphragm spring axially
against the cover via the adjuster ring and during
normal actuation of the clutch. As the linings
wear, the tendency of the diaphragm angle to
change causes an increase in the actuation force
required to operate the clutch. When this
increased effort exceeds the counter force of the
sensor spring, the diaphragm spring moves axially
towards the pressure plate until the original angle
is restored. At this point the actuation force
required drops to the level of the opposing sensor
spring force, restoring equilibrium with the
diaphragm spring at its new location.
During the axial movement of the diaphragm
spring, the increased distance between the spring
and cover is taken up by the adjuster ring. This
ring has fifteen raised segments, each having a
ramp profile which fits into a corresponding
shape in the clutch cover. When the diaphragm
spring moves axially for wear compensation,
three pre-loaded coil springs in the clutch cover
cause the adjuster ring to rotate, moving up the
ramps and taking up the extra distance between
the diaphragm spring and clutch cover.
Note that, in operation, the adjuster ring rotates
in a clockwise direction, as viewed from the
transmission. If a worn driven plate is replaced in
service and the clutch cover assembly is to be re-
used, the adjuster ring must be rotated back to its
pre-loaded position (see JTIS service instructions).
J.307.318
DUAL MASS FLYWHEEL AND CLUTCH ASSEMBLY
J.307.318
J.307.319
OPERATION OF SELF ADJUSTING CLUTCH
J.307.319
Dual Mass
Flywheel
Assembly
Self Adjusting
Clutch
Driven Plate
Concentric
Slave Cylinder
Adjuster
Ring
Conventional
Clutch
Sensor Spring
Diaphragm
Spring
Self Adjusting
Clutch
Diaphragm
Spring
