2011 FORD SUPER DUTY ENGINE USES NEW TORQSHIFT TRANSMISSION HARNESS
- The new 6R140 heavy-duty TorqShift® six-speed automatic
transmission is specifically designed to handle the increased torque
produced by the all-new Ford-designed, Ford-engineered and Ford-built
6.7-liter Power Stroke® V-8 turbocharged diesel and also will be mated
to the all-new 6.2-liter V-8 gasoline engine - The new
TorqShift transmission’s wider gear span, advanced controls that
optimize the shift schedule, reduced parasitic friction losses and
lower-rpm torque converter lock-up all contribute to improving fuel
economy in the 2011 Ford Super Duty - The new 6R140
transmission provides full SelectShiftâ„¢ capability and is available
with segment-exclusive Live Drive Power Take Off (PTO) with the new
diesel engine
DALLAS, Sept. 24, 2009 ““ All-new diesel and gasoline engines are key
reasons why the 2011 Ford F-Series Super Duty maintains best-in-class
towing and payload and adds enhanced off-road capability. Managing the
increased horsepower and torque is the all-new 6R140 heavy-duty
TorqShift® six-speed transmission, which delivers power quickly and
seamlessly while maximizing fuel economy.
“Our new transmission perfectly complements our new diesel and
gasoline engines to give the customer the best powertrain for Super
Duty applications,” said Al Bruck, 6R140 transmission engineering
manager. “Rigorous testing ensures our transmission and powertrain is
up to the challenge of even our most demanding Super Duty customers.
Overall, the 6R140 heavy-duty TorqShift six-speed transmission enables
greater customer capability, efficiency and control than ever before.”
Creating a transmission to serve both diesel and gasoline engines in
a Super Duty application is a challenging proposition because the
gearbox needs to deliver the substantial low-rpm torque produced by the
diesel engine and efficiently use the higher rotational speeds of the
gasoline engine. The solution was to use a proven architecture, but
adapt it for heavy-duty use.
Lepelletier powerflow: New application of tried-and-true system
Ford’s 6R140 TorqShift transmission uses a Lepelletier-style powerflow,
which is a proven technology in rear-wheel-drive vehicles but not
typically used with larger diesel engines. A key benefit of the
Lepelletier architecture is that it reduces the complexity in
connecting the gearsets and clutches. The six speeds require only five
clutches, and the speeds of the clutches relative to one another are
low, increasing the efficiency of the system.
To handle the torque of the 6.7-liter Power Stroke V-8 turbocharged
diesel, Ford strengthened the system by employing a unique powder-metal
carrier in the compound Ravigneaux planetary gearset. The carrier
consists of four pressed powder-metal components sinter-brazed together
to form a rigid, power-dense structure. This solution ensures
robustness and makes the architecture compatible with both the diesel
and gasoline engines. A Ford-patented rocker one-way clutch is
integrated with the carrier and helps improve 1-2 shift quality through
the gearset.
“With this architecture, the new transmission can handle the
enormous low-end torque produced by the new diesel engine as well as
the high speeds produced by the new gas engine,” Bruck said. “The
sinter-brazed gearset enables more torque capacity and greater engine
speed capability.”
A deep first gear ratio and two overdrive gears create a wider ratio
span. This, combined with available lower axle gear ratios and a
control system that automatically selects the most efficient shift
schedule, provides an outstanding combination of pulling power and fuel
economy.
“Our first gear ratio is a fair amount deeper than our competitors,
so customers will get improved off-the-line performance,” Bruck said.
“The six ratios we’ve selected provide greater overall span and better
overdrive performance, which reduces engine speed in highway conditions
and improves fuel economy.”
“Because we have six gears, we make smaller steps gear to gear,
which helps keep the engine in its sweet spot in terms of performance
and efficiency.”
Six-speed gearbox offers best of automatic, manual transmissions
The 6R140’s heavy-duty TorqShift six-speed transmission balances
convenience and control by automatically shifting during routine
operation and also allowing complete manual control. It features
SelectShift Automatic transmission functionality, which includes both
Progressive Range Select and manual functions.
With Progressive Range Select, a toggle on the shift lever allows
the customer to reduce the range of available gears while in Drive.
When the customer “taps” down into Range Select mode, the display shows
the available gears and highlights the current gear state. This feature
allows the driver to limit use of upper gears when heavily loaded or
while towing on grades.
For full manual function, customers also can pull the shift lever
into “M” for manual mode and use the same toggle switch to select the
gear desired. The display will show the selected gear, and the control
system will lock the torque converter and hold that gear for a full
manual transmission feel.
Proven Tow Haul Mode: Taken to the next level
The 6R140 transmission also features standard enhanced Tow Haul
capability, which provides better control when hauling a heavy load or
towing a trailer, especially when going down grades. The improved
system uses an array of sophisticated electronic sensors to better
predict the driver’s need for a downshift to provide engine braking and
enhanced control.
Torque converter provides connected feel and better efficiency
The torque converter of the 6R140 transmission is designed to be
accurately controlled and efficient. A closed-piston design provides
precise control of the lock-up clutch. Its torque multiplication is
matched with the rest of the powertrain for better off-the-line
performance, but that’s only the start. Once under way, a long-travel,
high-capacity turbine damper allows the torque converter to dampen out
the extreme torsional force produced in particular by the new, more
powerful diesel engine.
“This damper allows us to lug down to 900 rpm while our competitors
lug to around 1,100 rpm,” Bruck said. “This technology allows us to
stay locked more, which means the engine can run at a lower rpm and get
better fuel economy.”
Live Drive PTO: Power whenever the engine is running
Another example of taking a proven technology and applying it to the
Super Duty to improve customer productivity is the availability of
segment-exclusive Live Drive PTO (Power Take Off). On 2011 Ford Super
Duty diesels with the PTO prep option, the PTO output gear is linked
through the torque converter to the engine crankshaft. This allows the
transmission to power auxiliary equipment such as snowplows, aerial
lifts, cement mixers, tow truck lifts or dump trucks. The power is
available any time the engine is running.
Pioneered on agricultural applications, the Live Drive feature is
particularly useful when mobile PTO function is required during
start-stop operations, such as salt spreading or snow plowing. “A fully
functional Live Drive mobile PTO will allow Super Duty customers to
take full advantage of the equipment on their trucks,” said Bruck.
Durability testing in the lab and on the road
The 6R140 transmission has undergone extensive durability and
reliability testing in Ford’s supercomputers, in the lab and on the
road to ensure customer satisfaction. Extensive computer-aided
engineering was completed before the hardware phase began for improved
efficiency in terms of time and reduced failures.
Once the analysis was complete, physical testing in the laboratory
included running the new transmission 24/7 while mated to both engines
to help ensure real-world durability.
The transmission was rigorously tested ““ at unloaded and maximum GCW
(Gross Combined Weight) duty cycles ““ for 250,000 equivalent miles to
replicate what the most demanding, harshest Super Duty customer can
dish out.
The 6R140 heavy-duty transmission will be built at the Sharonville (Ohio) Transmission Plant.
