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Dual Mass Flywheel And Towing


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#1 TrimWizard

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Posted 31 May 2009 - 05:15 PM

Hi

We are new to caravaning and have allready had to change our Ford C-Max 1.6TDCI as it was struggling to get get going on hills towing 1200KG, even though it was rated to tow 1300KG. We got a nasty smell a couple of times and when I found that it would cost in excess of 700 to replace the clutch & Dual Mass Flywheel (DMF) we decided to get a better tow car before the DMF & Clutch failed.

So we bought a 54 reg VW Passat Highline estate 130TDI with 74,000 miles on the clock. This has no problem getiing going on hills B) But we have noticed that there is a judder when pulling away in 1st and been informed that DMF is on way out. The judder is not present when towing the caravan though.

I have googled DMF I have found that most manufactures have problems with DMF's including Porsche and one of the worst is Ford.

Does towing a caravan have a big impact on DMF & clutch wear issues?

I know it will have an impact on wear of the parts, but I wondered if anyone knows how much. My neighbour has a 51 plate Bora 130TDI that he uses to tow loads and he has just had his orginal clutch replaced at 130,000 miles, but not the DMF.

Our DMF & Clutch are being replaced this week, if I can get another 74,000 miles from the replacement I will be happy. Shame though, as all the VW's I have had before used to get well above 100,000 miles before needing a new clutch! That is progress for you :huh:

Cheers

Andy

#2 oldboy

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Posted 31 May 2009 - 08:09 PM

I suppose towing does put a lots of loads on the DMF, but you can't really tell when the clutch will go. on my last Mondeo it went at 78000 miles.

#3 Wingco

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Posted 31 May 2009 - 09:51 PM

The dual mass flywheel is, essentially, two flywheels bonded together with a semi-flexible adhesive (this is a very simplistic explanation). The idea is that the "second" flywheel can absord some of the vibrations that would occur at resonant frequencies of the engine, and thus make it smoother. It is supposed to make a diesel engine as smooth as a petrol. For some reason Porsche also used it on their 964 version of the 911 and had awful problems to start with.

The critical part is that the two are bonded together and the bonding process is heat sensitive. Basically, if you overheat the flywheel then you may well irreparably damage the bonding - and this is when DMFs fail.

Avoid slipping or riding the clutch; this is what gets flywheels hot. It really is a matter of driving technique; slip the clutch just enough to get the outfit moving and then try to release the clutch pedal completely, without stalling the engine. If you are one of those drivers who regularly cooks clutches then the chances are that you are going to suffer DMF failure.

#4 bilbo

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Posted 31 May 2009 - 09:52 PM

Reversing seems to do the most damage.

I burnt a clutch out on a mondeo when new to towing, up hill and around a bend.

Changed to a passat and had no problems since in 6 years although its time to change again soon 129000 on the clock.

#5 fleetwoodman

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Posted 31 May 2009 - 11:59 PM

I dont think you can ever tell when a DMF is going to go. I had a ford galaxy MK2 which had one. The diesel galaxy engine in these are not ford they are VW. If anyone needs to buy one i would suggest trying GSF first as if you go to the dealers you will pay over the odds for one. I think i paid 330 for a clutch and DMF as it was better to change this at the same time. My galaxy had done 165,000 miles when the work was done.

#6 TrimWizard

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Posted 01 June 2009 - 06:35 AM

Thank you for the replies.

I have a new DMF & Clutch that I bought them from GSF for half the VW price! Luk & Sachs parts, so exactly the same as VW parts, but no badge.

I have had a look at the DMF and you can move the inner flywheel (the part that contacts the clutch) by hand. It appears to be sprung loaded.

I did toy with replacing the DMF with a solid conversion, but have heard that can introduce vibration so decided to give a new DMF a go. If it fails prematurley I will go with a solid replacment. But if the new one does another 74,000 miles I will not unhappy as that is well over 5 years motoring away.

Cheers

Andy

Edited by TrimWizard, 01 June 2009 - 07:21 AM.


#7 Lee E

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Posted 01 June 2009 - 02:42 PM

I have a skoda. It is 3.5 years old with 78K on the clock. It has never missed a beat re: clutch/DMF. I have towed in reverse which does make the clutch stink but it has never failed or had any signs of failing.

Regards
Lee

#8 ChrisUK

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Posted 01 June 2009 - 03:11 PM

I try to treat the clutch when towing very carefully, like Winco. I try hard to look ahead at the traffic to give me a rolling start at the lights etc. Reversing seems to be a particular problem with modern cars, someone wrote somewhere that modern gearboxes full of 6 gears end up with a highish reverse ratio for some technical reason forcing you to slip the clutch alot. I now try to avoid reversing with the car and use the motor mover. So much so that I have probably lost the knak of reversing the caravan. I think the answer is to go auto I recently changed my car but was not able to unfortunately for other requirements.

#9 GMC

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Posted 01 June 2009 - 05:12 PM

I try to treat the clutch when towing very carefully, like Winco. I try hard to look ahead at the traffic to give me a rolling start at the lights etc. Reversing seems to be a particular problem with modern cars, someone wrote somewhere that modern gearboxes full of 6 gears end up with a highish reverse ratio for some technical reason forcing you to slip the clutch alot. I now try to avoid reversing with the car and use the motor mover. So much so that I have probably lost the knak of reversing the caravan. I think the answer is to go auto I recently changed my car but was not able to unfortunately for other requirements.


You're not the only one Chris. I have a healthy respect or my clutch (and my wallet) and invariably use the motor mover whenever any manoeuvring or levelling is required.

#10 TrimWizard

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Posted 01 June 2009 - 05:19 PM

You're not the only one Chris. I have a healthy respect or my clutch (and my wallet) and invariably use the motor mover whenever any manoeuvring or levelling is required.


I would love to fit a motor mover to our caravan, but it is a 1993 Elddis Jetstream, and although in super condition I think spending that amount of money on it would be a waste as it will be lost when the caravan is sold or part exchanged against another one :huh:

By the way, how much is a motor mover? Are they easy to fit? Wiring should be OK as I am an auto electrician ;)

#11 Mickyblueyes

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Posted 01 June 2009 - 05:30 PM

Movers can be had (single axle) from about 5-600quid are fairly straight forward to fit, if you read the instructions don't rush, and know one end of a spanner from another, taking the electrics as a given if you an auto sparky, (lets face it it's only a HD power feed from battery). A spare pair of hands helps a lot to hold stuff whilst fiddling.

Once you have one there is no reason why you cant move it on to a new van/next van or sell S/H.

#12 RADIOTWO

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Posted 01 June 2009 - 05:49 PM

I would love to fit a motor mover to our caravan, but it is a 1993 Elddis Jetstream, and although in super condition I think spending that amount of money on it would be a waste as it will be lost when the caravan is sold or part exchanged against another one :huh:

By the way, how much is a motor mover? Are they easy to fit? Wiring should be OK as I am an auto electrician ;)


Hi Trimwizard

Two things, first you have already got the bits, but my son who has a Ocativa need a new clutch he could
not afford it and was told about the single mass flywheel, so he had that fitted, a lot cheaper and has had
no problems since, thats a bout 12 months for him and at least 12K

The other thing, the Mover, Powewheel used to do s/h ones at about half price, and only 3 years warranty
instead of five, don't know if they still do or not, I bought one three years ago, but you mention about getting
rid of your caravan , just take it off and refit or sell

Radiotwo

#13 Jaydug

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Posted 01 June 2009 - 06:51 PM

Does towing a caravan have a big impact on DMF & clutch wear issues?


I'm inclined to think not. My own towcar has pulled my van to southern Spain and back four times now - 17000 of its 55000 mile total. As others have said, DMFs don't like too much sudden strain put upon them. Of the two Citroen cars that I've heard of with failed clutches, one driver admitted to racing down hills then just before a roundabout, slipping the gearbox into a lower gear. The other driver enjoyed his 'drag-racing' starts.

The practise of replacing the DMF with a solid flywheel is thought by some mechanics not to be a good idea since the power shock normally absorbed by the DMF is instead transfered to the transmission or timing belt.

#14 TrimWizard

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Posted 02 June 2009 - 07:08 AM

Clutch has been fine reversing, but then we do try to go to sites that are level and our storage site is also level :D

The first site we stayed at required putting one side of the caravan up 5 inches, that was the first time we made the C-Max clutch stink. We used 2 plastic wheel ramps on top of each other that meant you had to raise the van slowly, and had to slip the clutch to do so. I now have several bits of 6 x 2 planks of wood for leveling that are easy to tow forward onto as they are long enough to nor worry about shooting of the end. I use the plastic ramps to rasie van onto the planks, much better way.

Andy

#15 caprimadmick

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Posted 05 July 2009 - 04:31 PM

DMF failures on Fords are no worse than any other ! The Transit suffered massive warrenty claims mainly due to a lead right foot !!!

DMF's dont like abuse , they are a product of us wanting more refined motoring from a diesel .

When you factor in new injector's , DMF's , fuel pumps and air flow meters for modern diesels . . . . I'm glad I tow with a petrol B)

#16 jan69c

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Posted 05 July 2009 - 05:32 PM

I have been driving a Skoda Octavia, in fact the taxi company I have been working for has a huge fleet of them. The lads that maintain the fleet reckon you should get 120 k out of a clutch. However it depends on driving style. if you have a heavy right foot, and want to get away from the lights like the Stig on the Top Gear test track they can fail within 10 k. One driver was recently sacked for abusing the cars. Incidentally, the last Skoda I used had over 300 k on the clock, and according to the maintainance records was on its 3rd clutch.

#17 logiclee

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Posted 07 July 2009 - 02:51 PM

DMF failures on Fords are no worse than any other ! The Transit suffered massive warrenty claims mainly due to a lead right foot !!!

DMF's dont like abuse , they are a product of us wanting more refined motoring from a diesel .

When you factor in new injector's , DMF's , fuel pumps and air flow meters for modern diesels . . . . I'm glad I tow with a petrol B)


You're correct Ford DMF failure rates in diesel saloon cars are pretty average when compared to other mainstream manufacturers.

But remember most bigger petrol cars have them too, certainly all Mondeo's post 2001 have them for a start.

There is a huge difference though, DMF's smooth out the torque pulses that 4 stroke internal combustion engines produce. But the higher the torque the worse the shock, the slower the speed at which the torque is produced the more work the DMF has do to and the fewer the cylinders the more pronounced each shock is with no overlap.
So worst case for a DMF is the very common high torque 4 cylinder Turbo diesel. Stick a caravan on the back and you are having to put more torque through the DMF. It's not just a matter of gentle clutch work DMF's take abuse during normal driving.

DMF failure is no where near as common on petrol varients as the 4 cylinder versions have far less torque usually. Bigger capacity petrols that do have peak torque levels that rival diesels are usually large capacity V6's so have more cylinders to reduce the pulse level and give pulse overlap to reduce the work the DMF has to do. Maximum torque is usually produced higher in the rev range which again gives the DMF an easier life.
DMF failure on petrols is not unheard of but it's quite rare unless the cars done mega miles.

It's not just DMF's that have been caught out with the 4 cyinder Turbo Diesel issue either. The later 2.8CRD Jeep Cherokee was fitted with an autobox that had a torque rating far higher than the engine could produce and worked fine on big V8 petrols. The diesel engine started stripping the lockup clutches and destroying gearboxes. Jeep found the shock loads from the 295lbft @1800rpm 4 cylinder diesel was to blame, the torque convertor and lockup clutch just couldn't cope with the shock loading the torque pulses were causing.
Jeep ended up issuing a world wide recall replacing all the Torque Converters and more importantly altering the engine and gearbox maps so you couldn't get full torque when locked up. It really changed the car from being a beast to a revvy noisy no guts car. It caused Jeep massive problems in the USA with talk of a class action being brought against Jeep for downgrading customers vehicles, just google Jeep Liberty Torque Converter recall if anyone's interested.

Cheers
Lee

Edited by logiclee, 07 July 2009 - 03:11 PM.





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