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Ford DPS6 Transmission
March 14,
2016
LEONARD HOWE
AUTO 365
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TABLE OF CONTENTS
HISTORY AS WE KNOW IT ................................................................................................ 2 OVERVIEW ...................................................................................................................... 3 SHIFTING AND TRANSMISSION CONTROLS ...................................................................... 4 DPS6 POWERFLOWS ....................................................................................................... 7 UNIQUE SERVICE INFORMATION ................................................................................... 11 TECHNICAL BULLENTINS AND POPULAR CUSTOMER CONCERNS ................................... 13 CONCLUSION ................................................................................................................ 13 REFERENCES ................................................................................................................. 14
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HISTORY AS WE KNOW IT
Though the idea of dual-clutch technology has been
around since before World War II, prototypes were not
developed until the early 1980’s. Ford did not introduce a
dual-clutch transmission into production until 2008. At that
time, Ford’s first dual-clutch transmission, the DPS6, was
included as an option for the international versions of the
Ford Focus and Ford C-Max (Dual-clutch transmission, 2016).
In 2010, the DPS6 was finally introduced in North America
through the 2011 Fiesta (Abuelsamid, 2009). It continues to
be used today in North America as an option in the Fiesta
and Focus for select engine sizes and trim packages.
The name DPS6 indicates that the transmission is a
Dual-Clutch, PowerShift transmission with 6 forward speeds.
The DPS6 is also known as the 6DCT250 transmission by
Getrag. This transmission was a product of a joint venture between Ford Motor Company and Getrag.
The Getrag Ford Transmissions venture first began in 2001 and continues today (Getrag, 2016). Getrag’s
nomenclature provides further insight. A 6 speed Dual-Clutch Transaxle with 250 N.m. of max torque
capacity (roughly 184 ft. lbs.) (Getrag, 2015).
Though there have been some complaints of bumpy programming and other minimal issues, for
the most part the transmission has been very successful. It provides a sporty feel for consumers as well
as excellent fuel economy through its light weight and low impact design.
Year Model Engine Size
2011 Fiesta 1.6L
Fiesta 1.6L
Focus 2.0L
Fiesta 1.6L
Focus
(Except ST)2.0L
Fiesta
(Except ST)1.6L
Focus
(Except ST)2.0L
Fiesta
(Except ST)1.6L
Focus
(Except ST)2.0L
Fiesta
(Except ST)1.6L
Focus
(Except ST)2.0L
2008 - Present: Transmission has been available in
other International models
Source: MotoLogic.com
2012
2013
2014
2015
2016
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This transmission has also been used by other vehicle manufactures, including Volvo, Renault,
and BMW. The main difference between the transmissions provided to the different manufacturers has
been in their software setup to accommodate differing sensors and systems (Getrag, 2016).
OVERVIEW
The DPS6 has a fairly simple design. It is literally two manual transmissions in one unit. There are
two clutches, two input shafts and two output shafts. Also contributing to the simplicity of the unit,
there are no oil or transmission fluid pumps, or hydraulic valves or valve bodies. The gears inside the
transmission are splash lubricated, just as moving parts are inside a manual transmission. The fact that
the transmission does not require a pump to move fluid reduces the amount of load on the engine. The
use of electronically controlled clutches rather than a torque converter also implies that there is less
slippage and direct torque from the engine to the drivetrain can be achieved 100% of the time. This
greatly increases fuel economy.
Another positve lies in the reduction of overall fluid capacity. Where hydraulically controlled
transmissions will often require upwards of seven quarts of transmission fluid to maintain hydraulic
pressure behind pistons and within clutches and the torque converter, the DPS6 only requires between
1.7 and 1.9 quarts of its specified transmission fluid. This greatly reduces the cost of transmission fluid
exchanges. The reduced amount of fluid also decreases the weight of the transmission considerably.
With all the mechanical part and fluid reductions, the total weight of the DPS6 measures in at
about 160 lbs. with fluid (Ford, 2010). This is a dramatic decrease compared to the previous
transmission used in the 2010 Ford Focus, the 4F27E, which weighs in at 208 lbs. drained and without
the torque converter (AutoZone, 2016).
Without the hydraulic controls available from a valve body, there still needs to be a way to
adjust clutch timing and gear shifting. This control is provided through the software programmed into
the TCM. As new conditions are encountered and new applications are being accounted for, engineers
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are able to modify the programming to adjust shift timing and clutch application to ensure that shift feel
is appropriate. The software also enables engineers to modify dreaded noise vibration harshness (NVH).
SHIFTING AND TRANSMISSION CONTROLS
Though there are few articles specifying exactly how the DPS6 functions, online diagnostic
software provides crucial information from Ford regarding how shift points are achieved and the most
accurate descriptions of how the transmission operates.
There are several unique transmission controls in the DPS6 transmission that enable its manual
transmission base to function automatically. The Transmission Control Module (TCM) in particular
provides all the programming necessary to ensure accurate shift points. The TCM is bolted to the case of
the transmission. There are also two motors integrated into the TCM that protrude through the
transmissions interior housing to rotate gears. These gears, now on the inside of the transmission
housing, rotate other sets of gears, which in turn rotate two gear selection drums. Each gear can provide
a max shifting force of 337 lbs. to move shift forks when needed. (Ford Motor Company, 2013)
The sides of each of these drums have grooves which act as tracks. As the drums are rotated by
the TCM, the transmission’s shift forks and synchronizer sleeves are slid into place over their respective
Item Description
1Gear Selector Drum B
with Spur Gear
2Selector Fork - Reverse
Gear/4th Gear
3 Selector Fork - 3rd Gear
4 Selector - 1st/5th Gear
5Gear Selector Drum A
with Spur Gear
6Selector Fork - 2nd/6th
Gear
Source: MotoLogic.com
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dog clutches, which lock the appropriate gears to the appropriate output shaft.
The TCM is also used to control clutch engagement via two separate clutch force motors. These
motors are mounted to different sides of the transmission case and protrude to the inside of the bell
housing, just behind the dual-clutch assembly. They each move their own electromechanical lever
actuator which presses against the appropriate clutch springs to engage the appropriate clutch as
determined by TCM programming and input values.
There are several direct input sensors to the TCM that allow it to determine what the best
output operation should be. Input shaft speed (ISS) sensor A is used to measure the speed of 3rd gear on
output shaft B. It is also used to determine which direction the output shaft B is rotating. ISS sensor B is
used to determine the speed that output shaft A is rotating by measuring the speed of 4th gear on
output shaft A. The single output speed sensor (OSS) helps to determine output speed by measuring the
velocity of the differential. The transmission range (TR) sensor is used to provide information to the TCM
regarding the position of the gear selector lever, which in turn allows the vehicle to be started or
illuminates the reverse lamps.
Hall effect sensors incorporated into the gearing side of the TCM are used by the TCM to
determine gear selector drum position. There are also Hall effect sensors in each clutch force motor to
determine clutch engagement or disengagement. These Hall effect sensors serve an important role
when it comes to the TCM’s adaptive controls. As the clutch linings wear, the TCM will be able to
account for that because of these sensors.
There are also several inputs that are sent to and from the TCM on the HS-CAN network. This
includes information to and from the Powertrain Control Module (PCM), Anti-Lock Brake System (ABS)
module, steering wheel rotation sensor, Body Control Module (BCM), and the Instrument Cluster (IC).
The IC communicates indirectly with the TCM through the BCM. Information is shared between the BCM
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and IC via the MS-CAN before that information is sent from the BCM to the TCM over the HS-CAN, or
vice versa.
The PCM provides data regarding engine temperature, speed and torque. Throttle position and
outside air temperature are also provided through the PCM. Vehicle speed and braking events are
provided to the TCM from the ABS module. The steering wheel rotation sensor is used by the TCM to
prevent any upshifts or downshifts when the vehicle is going around hard corners. This feature can be
key in ensuring that the driver is able to maintain control while cornering.
Though the DPS6 is essentially two manual transmissions in one, the average vehicle owner
would expect that the transmission perform more like an automatic transmission as there are no clutch
pedals or a manual gear shifting lever (unless the vehicle is equipped with the Select-Shift lever, which
substitutes the L range for S and allows the driver to manually select the desired gear). One
characteristic that would be expected in an automatic transmission is a limited reverse rollback when
parked uphill on an incline. This is achieved through an optional feature called “Hill Start Control”. In hill
start control mode, first gear is preselected and the brakes are held automatically until the input from
the accelerator pedal, as well as load of the engine, indicates that engine torque is high enough to move
the vehicle forward.
A forward creep at a stop on level ground might also be an expected characteristic of an
automatic transmission that is not generally available in manual transmissions. This is achieved by
electronically controlling clutch A slippage in first gear when the brake has been released until higher
demand is deemed necessary. When it becomes obvious that the driver intends the vehicle to move
forward, clutch A is commanded by the TCM to be fully engaged. The wear that would result from such
clutch slippage seems to have been taken into account as service specifications indicate that clutch A
has a new thickness of 26 mm compared to clutch B’s 15 mm thickness (Ford Motor Company, 2013).
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Likely in an attempt to reduce the number of redundant sensors, Ford seems to have come up
with an innovative method of calculating clutch temperature. Excessive clutch temperature will cause
damage to the clutches and should be prevented. The temperature is based on engine torque and rpm
values from the PCM. Rotational speed signals from the ISS 1, ISS 2, and OSS sensors are directly
inputted into the TCM and make the model. There is also a calculated clutch torque value that plays into
the equation. When the TCM detects the clutches are hot, “Hot Mode” is enabled and the clutches may
be disengaged altogether until they have been able to cool down. The driver will then be notified of why
the vehicle no longer moves with a series of messages in the IC display (Ford Motor Company, 2013).
DPS6 POWERFLOWS
As previously described, there are clutch force motors that apply or release engaging bearings
against the clutch pressure springs within the dual-clutch assembly which eliminate the need for a driver
operated clutch pedal. Each clutch has its own force motor that allows the clutches to release and
engage independently, but also simultaneously. This greatly reduces torque loss that is prominent in
today’s hydraulically controlled transmissions. The following diagram depicts the movement required to
engage or disengage the clutch discs.
Item Description
A Clutch at rest (Open)
B Clutch A Closed
1 Pressure Plate B
2 Clutch Disc B
3 Driving Disc
4 Pressure Plate A
5 Clutch Disc A
6 Input Shaft A
7 Input Shaft B
8 Lever Spring B
9 Lever Spring A
Source: MotoLogic.com
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As described by Lance Wiggins in his article, “Let’s Play Ball: Ford’s Dual Clutch Is Shifting Into
the Future,” this dual-clutch system is described as an active clutch. In other words, “contact pressure is
zero if no force is applied to the lever springs,” and provides an extra layer of safety in the case that a
clutch force motor fails (Wiggins, 2013). This is especially important as the driver may not appreciate a
sudden lurch if a failure occurred and the clutch locked up. Injury might even occur at higher speeds.
The dual-clutch design requires there to be two input shafts. When Clutch A is applied, Input
Shaft A (the inner input shaft) will transfer torque from the engine through the odd gears to the
differential. Input Shaft A and the odd gears are represented in pink in the following diagram. When
Clutch B is applied, torque is transferred through Input Shaft B (the outer input shaft) and through the
even gears represented in blue. Input Shaft B is also responsible for creating Reverse (the silver gears).
It should be noted that the Differential gears are continually meshed with the green pinion gears
of both output shafts. When one output shaft is engaged, however, the other output shaft will be
freewheeling.
Item Description
1 Differential
2 Reverse Gear
3 4th Gear
4 3rd Gear
5 1st Gear
6 5th Gear
7 6th Gear
8 2nd Gear
9Input Shaft B - 2nd,
4th, 6th, and Rev.
10Input Shaft A - 1st,
3rd, and 5th
Source: MotoLogic.com
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First Gear
To engage first gear, the TCM controlled gear selector
drum A rotates to the 10˚ position, moving the 1st/5th
synchronizer sleeve into position over the first gear dog clutch and
gear. The Clutch A force motor then engages Clutch A to
transfer torque though input shaft A and then to the differential
through output shaft A pinion. First gear provides a 3.917:1 gear ratio.
Second Gear
Second gear is achieved when gear selector drum B
is rotated by the TCM to the 100˚ position. This moves the
2nd/6th selector fork and synchronizer sleeve into position
over the second gear dog clutch and gear. The clutch B force
motor is then engaged to transfer torque through input shaft
B and then to the differential though the output shaft A
pinion gear. Second gear provides a 2.429:1 gear ratio.
Third Gear
Third gear is engaged when the TCM rotates gear
selector drum A to the 145˚ position which causes the 3rd gear
selector fork and synchronizer sleeve to move into position over
the third gear dog clutch and gear. The Clutch A force motor
then engages input shaft A which transfers torque to the
differential through the output shaft B pinion gear. Third gear provides a
1.436:1 gear ratio.
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Fourth Gear
When gear selector drum B is rotated by the TCM to
the 190˚ position, the Reverse/4th gear selector fork and
synchronizer sleeve move into position over the forth gear dog
clutch and gear. The clutch B force motor then engages to
transfer torque through input shaft B and then to the
differential through the output shaft B pinion gear. Forth gear provides
a 1.021:1 gear ratio.
Fifth Gear
To engage fifth gear, the TCM rotates gear selector
drum A to the 190˚ position. The 1st/5th selector fork and
synchronizer sleeve then move to engage 5th gear. The TCM
will then engage the clutch A force motor in order to transfer
torque through input shaft A and then to the differential
though the output shaft A pinion gear. Fifth gear provides a
0.867:1 overdrive gear ratio.
Sixth Gear
In order to engage sixth gear, the TCM rotates gear
selector drum B to the 280˚ position. The 2nd/6th selector fork
and synchronizer sleeve slide to engage the sixth gear. The clutch
B force motor is then engaged to transfer torque through input
shaft B and to the differential through the output shaft A pinion
gear. Sixth gear provides overdrive at a gear ratio of 0.702:1.
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Reverse
Reverse is the most complicated of the gears just
because it utilizes gears on both output shafts. The TCM
rotates the gear selector drum B to the 10˚ position and moves
the Reverse/4th selector fork and synchronizer gear to engage
the reverse gear on output shaft B. Because the silver gear on
output shaft B (on top) is in mesh with the silver gear on output shaft A
(on bottom), when the clutch B force motor engages, torque is transferred through the output shaft A
gears to output shaft B, and finally to the differential through the output shaft B pinion. All the while,
output shaft B is locked and output shaft A is freewheeling. Reverse provides a gear ratio of 3.508:1.
Park
When park is selected with the shift lever and the engine is running, the parking pawl is put into
place and first gear and reverse are selected as described previously by the turning of both gear selector
drums A and B. Both clutches are also applied while the engine is on. When the engine is turned off,
however, the clutches are opened and the only thing limiting vehicle movement is the parking pawl
attached to output shaft B.
UNIQUE SERVICE INFORMATION
The DPS6 requires certain procedures to be followed during service that may be different than
hydraulically controlled transmissions. For example, the way the fluid is checked is largely similar to a
Honda or Accord vehicle. There are no internal fluid pumps that suck fluid through the system during
transmission engagement. Therefore, the fluid should be checked on level ground, in neutral, with the
engine off. Fluid should be added or allowed to drain from the fill plug on the side of the transaxle until
the fluid reaches the bottom of the fill hole.
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Because the system is splash lubricated and because there are no external oil coolers, cooler
lines, or torque converters, a flush merely consists of a simple drain and fill procedure. The fluid used
should be Motorcraft Dual-Clutch Transmission Fluid that meets Ford specification WSS-M2C200-D2.
Essentially, this a 75W-90 oil with special additives. Currently, there is not a valid substitute fluid
available in the United States.
Ford entertains that the DPS6 is even more manageable from a technician’s standpoint. Fluid
leaks and contamination are limited to a few oil seals, and most shifting issues can be resolved by
upgrading the TCM to the latest software version. However, if the front seal or dual-clutch assembly
does need to be replaced a special tool with Rotunda part number 307-675 must be used. This tool will
cost more than $400 and is specific to this transmission. The tool ensures that seals are set at the proper
depth and that the clutch assembly is removed and reinstalled properly to avoid vibration and clutch
shudder. Apparently, this transmission is extremely sensitive to installation procedures
(FordTechMakuloco, 2014).
If the transmission case needs to be opened up, the process of aligning all the parts to be able fit
them back into the case can be nearly impossible. A special assembly table (Rotunda part number 307-
680) is required to be purchased to keep all the shafts upright. The table can cost about $800 or more
depending on the source.
Fortunately, even though it may not be possible to remove the clutch without the clutch tool, it
is possible to keep everything together and inline by using the bellhousing as a holding table as Bill
Brayton describes in his article “Fun With Transmissions: DPS6: It’s a Stick Shift” from the June 2014
edition of Gears Magazine. It requires a few extra steps in order to flip all the components from the
main case to the bell housing. Some of these steps include removing holding pins that keep the
transmission components from dropping out of the main housing, but if the repair facility doesn’t
specialize in this particular transmission, it may be nice not to have to buy the tool (Brayton, 2014).
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TECHNICAL BULLETINS AND POPULAR CUSTOMER CONCERNS
Thus far, the majority of the issues with the DPS6 have been with regard to clutch shudder
issues. Some drivers have experienced a harsh shudder and lurching in reverse that would cause them to
fear parallel parking. The symptom is similar to what is experienced when a driver dumps the clutch too
quickly in a manual transmission vehicle while trying to maintain low engine speed.
A shudder related Field Service Action (FSA) included 14M02. FSAs are not TSBs, per se, and
reprogramming the TCM would usually only be performed if the customer complained of the issue, as
not all vehicles are necessarily defective. The reprogram would generally involve loosening clutch
application parameters to reduce shudder likelihood.
Another common issue for earlier vehicles included a transmission fluid leak from the front
input shaft seal. FSA 14M01 and TSB 15-0120 both addressed fluid leaks with the replacement of the
input shaft seal with a newer, more robust seal that would not leak. The customer would usually feel
clutch shudder when the seal would leak because the transmission fluid would soak the clutch lining and
create unintended slippage. (Markus, 2011)
CONCLUSION
The DPS6 had a rough start as engineers were still learning to open and close parameters to
meet the needs of countless driving situations. As time progressed, however, the DPS6 is remained a
fuel saving, light weight, sporty alternative to more complicated automatic transmission systems. Its
simple design works especially well with compact vehicle applications. It is also likely that this
transmission will continue to be a Getrag Ford Transmission jewel for years to come as fuel economy
and vehicle cost savings remain high priority.
If there is one thing to remember while working on this transmission, it is apparent that a
technician would need to understand the importance of following service manual procedures in order to
be successful.
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REFERENCES
Abuelsamid, S. (2009, January 21). Ford officially announces dual clutch PowerShift gearbox for 2010.
Retrieved from AutoBlog: http://www.autoblog.com/2009/01/21/ford-officially-announces-
dual-clutch-powershift-gearbox-for-201/
AutoZone. (2016). 4F27E Transmission. Retrieved from AutoZone:
http://www.autozone.com/drivetrain/automatic-transmission/all-trans-automatic-
transmission/68700_0_0/
Brayton, B. (2014, June). DPS6: It's a Stick Shift! Retrieved from Gears Magazine:
http://www.gearsmagazine.com/magazine/view/c682f48d-e3e9-4cf7-a15b-
573f3a8780cd#page6
Dual-clutch transmission. (2016, March 3). Retrieved from Wikipedia:
https://en.wikipedia.org/wiki/Dual-clutch_transmission
Ford. (2010). DPS6 PowerShift Transmission Game Changing Technology for Fuel Economy. Retrieved
from SlidePlayer: http://slideplayer.com/slide/3815051/#.VtocHSZ5LYc
Ford Motor Company. (2013). Transmission Description - System Operation and Component Description -
Desription and Operation. Retrieved from MotoLogic:
https://www.motologic.com/car/2014_fd_fiesta_5487/article/0af6511623d3c9f013f3aaf17cdb9
ccd?sit=/sit/all&ssc=/ssc/powertrain/transmission/automatic/trans_unit#
FordTechMakuloco. (2014, April 30). 2011 + Ford Fiesta & 2012 + Focus Shudder- Clutch Replacement.
Retrieved from YouTube: https://www.youtube.com/watch?v=YVJnNPbjjjs
Getrag. (2015, August). Product Brochure 6DCT150. Retrieved from Getrag:
http://www.getrag.com/media/products/powershift/6dct250/6DCT250.pdf
Getrag. (2016). History. Retrieved from Getrag: http://history.getrag.com/?lang=en
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Markus, F. (2011, December 23). Ford's Focus PowerShift Transmission Is Much Improved. Retrieved
from MotorTrend: http://www.motortrend.com/news/ford-focus-powershift-transmission-is-
much-improved/
Wiggins, L. (2013, September). LET'S PLAY BALL: Ford's Dual Clutch Is Shifting Into the Future! Retrieved
from Gears Magazine: http://www.gearsmagazine.com/magazine/view/90f3b947-b6ea-4671-
89da-26acffc3c201#page38
