Looming DMF Failure

Ultrasonic

atrixblue.-MFR-. wrote: »

do you believe everything that the interweb says?

Hardly! I think you've probably seen enough of my posts to know that critically assessing what I read isn't something that I struggle with .

Golf Bravo is doing a much better job of debating this issue than I could so I'll shut up and read with interest .

atrixblue.-MFR- wrote:

once in gear the DMF is engaged, if you have engine irregularity at 2000rpm there is something wrong with that engine, besides the SMF, and lets face it if you tumbling along in 3rd 4th or 5th gear at 2000rpm doing -15MPH what engine wouldnt struggle.

Although I will just add that driving along with a diesel engine at 2,000 rpm is hardly running at low revs and certainly shouldn't be reason for them to struggle. My car (with a DMF) does 2,000 rpm in 5th gear at 60 mph, and peak torque is at 1,900 rpm. In 3rd gear, 2,000 rpm is about 32 mph I think.

atrixblue.-MFR-.

GolfBravo wrote: »

Figure 5 illustrates the wide open throttle characteristic curve of a typical diesel engine. For a conventional drive train, the additional dynamic torques as a result of the irregularity are superimposed. Depending on the speed, they can generate more than 10 % additional load.

Source: Schaeffler



By my post? Immediate failure? Where does it say that?

Further reading:

Source: Schaeffler

i take on board the research and draw my own conclusion to it.

heres a company that spawned the DMF, it has its purpose.

over many years of the DMF being born, people are now reverting back to SMF due to costs of the DMF, LUK even produce DMF to SMF convertion kits! if the above was such a concern, and alarm would you think they would produce them?

the research was carried out by the company who produced the DMF, sales has no doubt slumped of the DMF since convertion kits have become widely available, i'll call the research informative but lacking the definitave independant proof,they cannot give a definate time scale or period over years to such of what they claim, what parts mainly were effected by the harmonic vibration excess and to what degree over how long a period their test were conducted, so i can only guess that they used a single engine bench setup and ran a test with DMF and with SMF and measured the harmonics and based on the above, then drew up a scientific theory.

your referance can be closely linked with using incorrect OIL

for e.g you can put 20/50 oil in a car, and run it all the time, it will affect the engine in the long term as its not to spec.

basically what the above states is as its not to spec it could affect the car long term but cant tell how long, what parts and how this differs between vehicles and engine sizes because the research didnt go that far or did not put a time scale to the damage because a.other factors play a role like engine wear and it could effectively take 100 years to create failure due to harmonic vibration.

like i said ive had noone complain of the above, my balance shaft split, my conrods suffered stress cracks, my timing belt snapped because of the SMF convertion my layshaft threw through the bell housing because of the SMF, the gearbox bearing dropped out, my driveshafts went because of the conversion, my stater motor teath shattered because fo the SMF convertion noone, has stated catagoricaly that SMF convertion has caused other damage as a result.

i always take research or claims like the above with a pinch of salt when it comes from the makers it screams weve done this research to keep the DMF production alive, stop converting to the cheaper solution when we want you to buy the dearest option especially when the company is selling its own line or SMF convertion kits!

sorry i cant take that research and call it through and non bias.

GolfBravo

atrixblue.-MFR-. wrote: »

over many years of the DMF being born, people are now reverting back to SMF due to costs of the DMF, LUK even produce DMF to SMF convertion kits! if the above was such a concern, and alarm would you think they would produce them?

They just don't want Valeo and Sachs to eat their lunch.

atrixblue.-MFR-. wrote: »

the research was carried out by the company who produced the DMF, sales has no doubt slumped of the DMF since convertion kits have become widely available, i'll call the research informative but lacking the definitave independant proof,they cannot give a definate time scale or period over years to such of what they claim, what parts mainly were effected by the harmonic vibration excess and to what degree over how long a period their test were conducted, so i can only guess that they used a single engine bench setup and ran a test with DMF and with SMF and measured the harmonics and based on the above, then drew up a scientific theory.

Do you really expect them to publish their durability testing results? And you expect the world's largest clutch manufacturer, with over 6000 employees working in R&D, to use a single bench setup for their durability testing?

The fact that you

sold over a 3 year period probably about 2000 SMF kits to replace a DMF ... i have never, not im my 3 year period had a warranty issue or heared of catastrophic failure of crank and gearbox or clutch as a direct result of excess vibration or excess loading on a gearbox or crank.

doesn't prove anything either. It only shows that no customer made a SMF complaint to a single retailer during that particular period of time.

The fact is that DMF dampens engine irregularity and reduces transmission loads. And you can draw your own conclusions from that.

atrixblue.-MFR-.

show me the hard fact evidence, independant EVIDENCE other than LUK bias research that suggests to me that they are trying to suade you from buying other producers of the SMF's and DMF's.

ofcourse they will put such statement out there to stop you buying non LUK produced parts or non OEM spec parts that they produce.

LUK are contradicting themselfs by producing the SMF kits and saying their bad for your car! buy our highly priced DMF's instead!.

there is no such thread on here relating to gearbox failure due to fitting a SMF kit, my BIL sold thousends been in the motor factor buisiness over a 18 years a long period in selling kits on a weekly basis with no such complaint.



tell my WHY LUK produce SMF kits for their applications for manufacturers, when they claim to such degree your engine is at such risk! the above is sketchy and bias.

heres valeo's version to pro's and cons of SMF v DMF and how they fully design and test every application.

http://www.valeoservice.com/data/master/webfile/16486400834F71D17D28D79.pdf

GolfBravo

atrixblue.-MFR-. wrote: »

tell my WHY LUK produce SMF kits for their applications for manufacturers, when they claim to such degree your engine is at such risk! the above is sketchy and bias.

heres valeo's version to pro's and cons of SMF v DMF and how they fully design and test every application.

To make money. Since all their competitors offer it, they have to offer it too to remain competitive.

The price difference between DMF + clutch kit and SMF conversion kit is only 10-20%. They do not offer it to save customers 10%, they offer it to save the cost of subsequent DMF replacements - when fitting your 3rd or 4th clutch you no longer have to buy a new DMF, you just buy a beefed up clutch compatible with SMF.

This is targeted specifically at drivers who struggle with their clutch technique (the main cause of DMF failure is overheating), and are expected to go through a number of clutches, eg: Ford Transit courier drivers.

Reduced long-term durability? Customers obviously don't care so why should LuK/Valeo/ZF care? It's sort of like VW now using the bottom of the range Valeo air conditioning compressors (around 20% less durable) to save money on their lower-spec cars - do Valeo care?

jase1

Cars with 100,000 miles rattle. I didn't think this was particularly classified information.

Retrogamer

jase1 wrote: »

Cars with 100,000 miles rattle. I didn't think this was particularly classified information.

It doesn't have 100,000 miles thought, it has 96,136...


To the people posting the helpful stuff surrounding SMF vs DMF and complications ect, really interesting reading. It's all older mechanical diesels i've driven until now so didn't even have ECU's let alone DMF's so good info.

scaredofdebt

My Mondeo 2.0 TDCI had its DMF fail at 170k, there was a slight vibration through the clutch pedal before that but it started doing that around 130k so I got plenty more out of it once I noticed the first signs.

No new starter motors required, it cost me £850 for a new DMF and a clutch, got another 35k out of it before the fuel pump went and I decided to bin it as it *might* have damaged the injectors.

There were no other symptoms apart from the slight vibration through the clutch, even went it failed I could still drive it although the clutch pedal took a few seconds to return to the usual position when I released it, so I decided that was time to spend the cash.

To answer the OP, at that mileage it would be considered normal wear and tear so unless you had literally only just had the car a few weeks there's no recourse, but no harm in asking of course!

jase1

If my 07-plate Mondeo's DMF goes the whole car will be going to the scrapper -- the bloody thing has more rattles, bangs and general crapness than anything else I've owned.

Never again another Ford -- that's two I've had now in a row that don't come close to the quality of the Japanese.

Retrogamer

scaredofdebt wrote: »

My Mondeo 2.0 TDCI had its DMF fail at 170k, there was a slight vibration through the clutch pedal before that but it started doing that around 130k so I got plenty more out of it once I noticed the first signs.

No new starter motors required, it cost me £850 for a new DMF and a clutch, got another 35k out of it before the fuel pump went and I decided to bin it as it *might* have damaged the injectors.

There were no other symptoms apart from the slight vibration through the clutch, even went it failed I could still drive it although the clutch pedal took a few seconds to return to the usual position when I released it, so I decided that was time to spend the cash.

To answer the OP, at that mileage it would be considered normal wear and tear so unless you had literally only just had the car a few weeks there's no recourse, but no harm in asking of course!

If it fails i should have recourse via the Sales of Goods act,
Goods sold must be fit for purpose and last a reasonable amount of time and if the fault happens before 6 months, it's on the onus of the trader to prove it failed through abuse / mis use rather than wear as far as i know.

I'm not confident i could use it just now as the noise isn't all that obvious yet. I plan to keep the car 5 years / 60k miles so i'm sure that it'll need done at some stage.