New Allison 1000 Transmission
Offers Six-Speed Performance and Range Selection
Mode
- First-in-class
six-speed automatic transmission with two
overdrive gears
- Engine speed
reduced by 250 rpm at 60 mph
- Enables improved
fuel mileage and range
- First-in-class
tap-shift range-selection feature allows driver
to easily select desired gears for greater
control
- Part of GM’s
rollout of 10 six-speed automatic transmission
variants by the end of the decade
PONTIAC ,
MICH. – The Allison 1000 transmission grows
from a five-speed automatic to a first-in-class
six-speed automatic for the 2006 Chevrolet Silverado
HD and GMC Sierra HD trucks equipped with the
Duramax 6600 6.6L V-8 diesel or Vortec 8100 8.1L
V-8. Also new for 2006, the Allison 1000 six-speed
features a class-first tap-shift range selection
function, as well as offering enhanced fuel mileage,
quietness and control. The range selection function
allows the driver to easily select the desired gears
to match driving conditions, such as towing a
trailer on a steep grade.
“Changes to the
Allison 1000 represent a ‘best of all worlds’
scenario,” said Kevin Wayman, Allison 1000 chief
engineer. “Performance, quietness and fuel mileage
are all enhanced without degradation to product
durability.”
The sixth gear –
essentially a second overdrive gear – enables a
wide, 5.08:1 overall forward gear ratio coverage and
allows the vehicle’s engine to operate at lower rpm,
particularly during higher-speed driving on highways
and freeways. Its 0.61 ratio sixth gear provides a
1550-rpm engine speed at 60 mph, compared with the
five-speed transmission’s 1800-rpm engine speed at
60 mph. The engine uses less fuel at lower rpm,
enabling increased fuel mileage and range. The
ratios of gears 1 through 5 remain the same as the
Allison 1000 five-speed, including the 0.71:1 fifth
gear.
A tow/haul mode is
retained on the Allison 1000 six-speed, but it is
complemented by a new range selection feature. It
allows the driver to select the desired gears, via a
thumb-activated switch on the shifter, providing a
feeling of enhanced control in unique driving
situations, such as towing on a steep grade. The
range selection feature holds the gear pre-selected
by the driver and electronic safeguards prevent the
transmission from being shifted in a manner that
could cause engine damage or loss of vehicle
control. Grade braking and cruise grade braking are
only available when the tow/haul mode is selected
and the transmission is not in the range selection
mode.
Diesel-engine
vehicles equipped with the Allison 1000 six-speed
feature cruise control grade braking. Working in
harmony with the tow/haul mode, the cruise grade
braking system will automatically downshift to help
maintain the pre-selected cruise speed when driving
on downhill grades.
A new low-traction
mode also is standard on vehicles equipped with the
diesel engine. When the driver selects second gear
while stopped and wheel slip occurs, the
transmission torque-manages the engine to limit tire
slip on slippery road surfaces.
In addition to the
sixth gear and range selection feature, the Allison
1000 also benefits from complementary upgrades that
include:
- Upgraded 310-mm
torque converter that improves torque capacity
- New 22-tooth
pump that improves NVH
- New solenoids
provide better converter lock-up control and
shift feel
- Upgraded
rotating clutch that improves torque capacity
- New A40, 32-bit
transmission control module
The Allison 1000 also
has a unique, GM-patented elevated idle mode, which
allows for faster interior warm-up of
diesel-equipped vehicles. The system, which is
activated through the vehicle’s driver information
center, is synchronized with the engine. When
elevated idle is active, the transmission increases
the load on the engine so that it will generate heat
more quickly and warm the interior in less time.
In 2004, GM
Powertrain announced plans to introduce 10 six-speed
automatic transmissions globally by the end of the
decade. The introduction of the new Allison 1000
six-speed automatic is another step towards
realizing that goal.
Allison 1000
Series Specifications (MW7)
|
Type:
|
Six-speed
rear-wheel-drive, electronically controlled,
automatic overdrive transmission with torque
converter clutch |
|
Engine range:
|
6.6L - 8.1L
|
|
Maximum engine
torque: |
650 lb-ft
|
|
Maximum gearbox
torque: |
900 lb-ft
|
|
Gear ratios:
|
|
|
First:
|
3.10
|
|
Second:
|
1.81
|
|
Third:
|
1.41
|
|
Fourth:
|
1.00
|
|
Fifth:
|
0.71
|
|
Sixth
|
0.61
|
|
Reverse:
|
4.49
|
|
Maximum shift
speed: |
4850 rpm
|
|
Maximum
validated gross vehicle weight: |
GVW
12000 lb – 3600 series
11400 – 3500 dually series
9900 – 3500 non-dually series
9200 – 2500 HD series
GCW
23500 lb – 3500 dually, 3600 series (6.6L
Duramax)
22000 lb – 3500 dually (8.1L), 3600 (8.1L),
3500 non-dually (6.6L Duramax, 8.1L) |
|
6-position
quadrant: |
P, R, N, D, M, 1
|
|
Case material:
|
die cast
aluminum |
|
Shift pattern:
|
(2) two-way
on/off solenoids |
|
Shift quality:
|
force motor
control / adaptive shifts |
|
Torque converter
clutch: |
Variable Bleed
Solenoid Control |
|
Converter size:
|
310mm (diameter
of torque converter turbine) |
|
Fluid type:
|
DEXRON® VI
|
|
Transmission
weight: |
dry: 150 kg (330
lb) |
|
Fluid capacity
(approximate): |
shallow pan: 12L
(13 qt.) (dry) |
|
Power take off:
|
provision
available |
|
Pressure taps
available: |
main pressure
|
|
Assembly sites:
|
Baltimore , Md.
|
|
Additional
features: |
Tap-shift range
selection mode; elevated idle mode; low
traction mode; shift stabilization;
tow/haul; grade braking |
|
Applications:
|
2006 Chevrolet
Silverado and GMC Sierra 2500HD and 3500
|
|
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