Team-BHP > Technical Stuff
Register New Topics New Posts Top Thanked Team-BHP FAQ


Reply
  Search this Thread
223,509 views
Old 28th September 2015, 14:46   #16
BHPian
 
ashua's Avatar
 
Join Date: Feb 2015
Location: Pune
Posts: 99
Thanked: 78 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Quote:
Originally Posted by arunphilip View Post
Previously, there was confusion over whether the 'sealed for life' constituted a warranty also; but none of the documentation indicated this was a warranty. However, a member has pointed out on either the Figo or Aspire thread that he'd seen material referring to a 10 year warranty (couldn't locate that post, sorry!). I've not seen any other confirmation other than this one item.
Quote:
Originally Posted by i74js View Post
The 10 year warranty was offered in Fiesta. Though even this warranty was not able to bring in fresh customers.

There is no news of such warranty on the new Aspire / Figo.
Here is the post that refers to Aspire AT DCT gearbox warranty. The quote is taken directly from the Ford Media release during the Aspire launch:
http://www.team-bhp.com/forum/indian...ml#post3779085

Here is the press release for the new Figo which also specifically mentions the 10 year 1 Lakh Km warranty on the automatic gearbox. http://www.india.ford.com/about/medi...=1249173475333

Last edited by ashua : 28th September 2015 at 14:50.
ashua is offline   (8) Thanks
Old 28th September 2015, 14:49   #17
BHPian
 
Join Date: Nov 2007
Location: Pune
Posts: 999
Thanked: 665 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Excellent thread arunphilip! Thanks for this! I always wanted to know the basic thing about this gearbox and this seems be the right thread. If I think of a typical manual gearbox setup, the engine sits on one side of the clutch and gearbox on the other. But in case of DCT how does is the engine connected to two clutches at the same time? Due to these multiple concentric shafts, I am unable to visualize it. Where does the crankshart connect to the clutch? Any diagramatic explanation would be highly helpful.
shipnil is online now  
Old 28th September 2015, 15:02   #18
Senior - BHPian
 
Join Date: May 2005
Location: Location
Posts: 5,766
Thanked: 9,054 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Very informative thread! I was of the impression that DCT too would be electro-hydraulic in operation but surprised to find that its not.

Another advantage apart from quick shifts of the DSG's electro-hydraulic unit is that hydraulic unit can in theory offer more clamping force for the clutch pack compared to a reduction gear based electro-mechanical unit. In practise with a DSG remap the clamping force is (can be) increased.

Mitsubishi EVO X has a Getrag twin wet clutch transmission which Mitsubishi calls SST. This Getrag is an electro-hydraulic unit utilising hydraulic pressure for shifting and holding clutch plates.

Quote:
Originally Posted by arunphilip View Post
particularly since wet clutches require oil lines from the engine.
The transmission oil, oil pump. transmission oil filter and transmission oil cooler are separate from the engine oil circuit.

Last edited by Sankar : 28th September 2015 at 15:04.
Sankar is offline   (8) Thanks
Old 28th September 2015, 19:37   #19
Senior - BHPian
 
Join Date: Jun 2015
Location: Chicagoland
Posts: 2,986
Thanked: 6,859 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

It's a fantastic piece of technology.
Even I've read that ford gives a 10 year/ 240000 km warranty on the gearbox. I think this warranty was there even in the 2011 fiesta.
landcruiser123 is offline  
Old 28th September 2015, 20:06   #20
BHPian
 
Join Date: Aug 2015
Location: Chennai
Posts: 60
Thanked: 130 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

The good thing about this transmission is we get good fuel efficiency and close to nil torque loss compared to conventional fluid coupling AT. How ever at extreme spirited driving and/or jump start and stop in bumper to bumper city traffic, the electronics get confused in adapting to driving habit and as a result clutch weakens soon and would start shuddering in 2nd and 3rd gears.
Living2Drive is offline  
Old 29th September 2015, 09:57   #21
BHPian
 
Join Date: Oct 2007
Location: Bangalore
Posts: 238
Thanked: 347 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

This being a dry system, what are the possibilities that it will suffer same problems of DSQ200.
I already saw potential of overheating being mentioned in the original post. Bangalore traffic will be real test for this.
If this box also suffers same failures as the famed VW dry box, the warranty will be quite handy.
CarJunki is offline  
Old 29th September 2015, 10:48   #22
RWD
BHPian
 
Join Date: Aug 2015
Location: Mumbai
Posts: 90
Thanked: 172 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Excellent thread arunphilip. Your efforts are much appreciated. Thanks.

In India, where the average ambient surface temperature, on a hot sunny day, in traffic conditions, can easily be 50 degree Celsius plus, I wonder if a dry clutch setup would be reliable in the long run. Especially in the start-stop-start-stop conditions. Guess we'll only know, once, Ford starts churning out volumes of this transmission. Hope it doesn't end up being another DSG.
RWD is offline   (4) Thanks
Old 29th September 2015, 12:15   #23
BHPian
 
Join Date: Nov 2012
Location: Hyderabad
Posts: 603
Thanked: 868 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Quote:
Originally Posted by RWD View Post
Excellent thread arunphilip. Your efforts are much appreciated. Thanks.

In India, where the average ambient surface temperature, on a hot sunny day, in traffic conditions, can easily be 50 degree Celsius plus, I wonder if a dry clutch setup would be reliable in the long run. Especially in the start-stop-start-stop conditions. Guess we'll only know, once, Ford starts churning out volumes of this transmission. Hope it doesn't end up being another DSG.
As an owner of EcoSport AT, I pray not. Ford sells the same gearbox in countries like Brazil, which can get quite hot and humid. I heard Sao Paolo is almost at hot and muggy as Chennai in summer (February, for them in the southern hemisphere). So it should be well tested by now. But, you never know.
Contrapunto is offline  
Old 29th September 2015, 20:09   #24
BHPian
 
Sudeep_Kimster's Avatar
 
Join Date: Aug 2015
Location: Pune
Posts: 121
Thanked: 292 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Fantastic Information
Thanks for sharing.

The 1D representation of the gear engagement and the working phenomenon has given me good insight to the working of a dual clutch system.

Just a question: Does any car have Dual mass flywheel and Dual Clutch together??
or this is some weird combination of me, as I know their requirements by cars are completely different.
Sudeep_Kimster is offline   (1) Thanks
Old 30th September 2015, 00:49   #25
Senior - BHPian
 
Mpower's Avatar
 
Join Date: Mar 2005
Location: Bangalore
Posts: 10,409
Thanked: 1,730 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Very informative thread and thanks for sharing.

Hopefully this will be the Dual Clutch for the masses given its affordable positioning (in its Figo avtar)

Quote:
Originally Posted by Sankar View Post
Very informative thread! I was of the impression that DCT too would be electro-hydraulic in operation but surprised to find that its not.

Another advantage apart from quick shifts of the DSG's electro-hydraulic unit is that hydraulic unit can in theory offer more clamping force for the clutch pack compared to a reduction gear based electro-mechanical unit. In practise with a DSG remap the clamping force is (can be) increased.
Higher clamping force so that car can handle more engine torque?

Last edited by Mpower : 1st October 2015 at 03:34.
Mpower is offline   (1) Thanks
Old 30th September 2015, 09:08   #26
Senior - BHPian
 
Join Date: May 2005
Location: Location
Posts: 5,766
Thanked: 9,054 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Quote:
Originally Posted by Mpower View Post
Higher clamping force so that car can handle more engine torque?
Yes, to mitigate the chances of clutch slip with high engine output setup. Not done normally.

Last edited by Sankar : 30th September 2015 at 09:10.
Sankar is offline   (1) Thanks
Old 30th September 2015, 12:38   #27
Distinguished - BHPian
 
khan_sultan's Avatar
 
Join Date: Apr 2006
Location: Noida/Bangalore
Posts: 4,925
Thanked: 5,853 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Very nice thread and great insights. I have a DCT Fiesta Petrol AT and love driving it in the city and even highways.

Few questions for the general community of interested readers here:

- I presume that these boxes are ECU controlled (and maybe even a separate ECU for the box), so is it possible for after market remaps of the boxes for a shift pattern that one would prefer? Any examples or such work done abroad?
I know of a TSB that Ford had done for the DCT in Fiesta for the clutch shudder/jerkiness in stop-go traffic. I had got it done and the DCT box behaved very differently after that TSB.

- These boxes will also have been tuned with the engine combo (So, my assumption is that the DCT box would be tuned differently for Aspire/Figo/Fiesta/Ecosport). If this assumption is correct, then any mod we do to engine (let's say FFE etc etc), will that impact the way DCT behaves/shifts for that particular car?

- Fiesta didn't come with that manual +/- shifter buttons on the DCT. Can these be retrofitted?
khan_sultan is offline   (1) Thanks
Old 30th September 2015, 13:32   #28
Senior - BHPian
 
Join Date: May 2005
Location: Location
Posts: 5,766
Thanked: 9,054 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Quote:
Originally Posted by khan_sultan View Post
- I presume that these boxes are ECU controlled (and maybe even a separate ECU for the box), so is it possible for after market remaps of the boxes for a shift pattern that one would prefer? Any examples or such work done abroad?
Yes there is a separate TCU (transmission control unit) for the box. Custom shift patterns should be possible to implement by an experienced and knowledgeable TCU remapper. HPA motorsports might be one such company abroad.

http://www.hpamotorsports.com/dsgtuning.html
Sankar is offline   (1) Thanks
Old 30th September 2015, 13:58   #29
Distinguished - BHPian
 
arunphilip's Avatar
 
Join Date: May 2007
Location: Bangalore
Posts: 1,989
Thanked: 6,171 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Quote:
Originally Posted by khan_sultan View Post
- I presume that these boxes are ECU controlled (and maybe even a separate ECU for the box), so is it possible for after market remaps of the boxes for a shift pattern that one would prefer? Any examples or such work done abroad?
As Sankar has mentioned, the gearbox has its own control logic called the transmission control module (TCM). I've covered this in the second post (which talks about the various components). Getrag has designed this gearbox to be quite independent of the engine, so while the TCM takes in various inputs from the ECU, it then interprets that input and applies its own internal logic to then perform gear changes (i.e. the TCM is only loosely coupled to the ECU).

Sankar has also pointed out tuning options for VAG's DSG series of gearboxes. However, I'm not aware of any tuning options for these low-torque DCTs for Ford. Higher performance PowerShift transmissions might have tuning options (such as the 7DCI700 used in various BMWs), but probably not the lower torque DCT we get in India.

Quote:
Originally Posted by khan_sultan View Post
I know of a TSB that Ford had done for the DCT in Fiesta for the clutch shudder/jerkiness in stop-go traffic. I had got it done and the DCT box behaved very differently after that TSB.
Thank you for that feedback, good to hear that. It will also reassure potential buyers of the DCT

Quote:
Originally Posted by khan_sultan View Post
- These boxes will also have been tuned with the engine combo. If this assumption is correct, then any mod we do to engine (let's say FFE etc etc), will that impact the way DCT behaves/shifts for that particular car?
The TCM/gearbox are loosely coupled to the engine, and the TCM takes as its input the engine speed (crank RPM) and engine torque (among other inputs), and drives its logic accordingly. In that respect, the gearbox will adapt to any changes in power output, particularly for 'stage 1' mods like FFE, CAI. However, if the power output has changed in terms of 'pattern' (e.g. peak torque coming in sooner), then the TCM would benefit even more from being reprogrammed to be aware of these changes. This is because factors like the upshift point are all based on the stock engine's performance, and you might realize even better performance in tuning the TCM accordingly. Then again, if you're looking at mods higher than stage 1, you probably shouldn't be targeting the PowerShift transmission - all reviewers acknowledge that it is a commuter transmission, not a performance one

Specific to India, I'd be curious just how extensively and how well the TCM has been adapted to the characteristics of the 1.5 TiVCT box we get here. Remember that this 1.5 TiVCT box is specific to India, and is derived from the international 1.6 TiVCT (those humourously inclined might joke that that the 100cc that was removed also took all the goodness out of that engine!)

Quote:
Originally Posted by khan_sultan View Post
- Fiesta didn't come with that manual +/- shifter buttons on the DCT. Can these be retrofitted?
It might not be that simple. The Fiesta not only came without the SelectShift +/- buttons, it also came with a subtly different gearbox - it has a low range (L) mode, instead of the Sport (S) mode that comes in the EcoSport and Figo siblings. At best, you might be looking at replacing the entire TCM to be able to use the +/- buttons. A replacement TCM costs approximately $800 in the US.
arunphilip is offline   (1) Thanks
Old 3rd October 2015, 19:19   #30
Senior - BHPian
 
Join Date: Jul 2009
Location: Calcutta
Posts: 4,668
Thanked: 6,217 Times
Re: Ford PowerShift Dual-Clutch Transmission (DCT) - A Technical Overview

Wonderful article.

I have a couple of questions though.
In the figure below, how is the torque being transmitted in the sloping section of the blue line?

Quote:
Originally Posted by arunphilip View Post
Quote:
Originally Posted by arunphilip View Post
Manufacturers use dry-clutches in low-torque applications,
What are the thought processes behind choosing a dry clutch vs a wet clutch?

Regards
Sutripta
Sutripta is offline   (1) Thanks
Reply

Most Viewed


Copyright ©2000 - 2024, Team-BHP.com
Proudly powered by E2E Networks