Replacement flywheel - dual mass or solid?

[daytona365]

Older stuff didn't have DMF BS and they were still smooth, cheaper and easier to fit, plus they didn't pull the transmission to pieces. Maybe because they were built right/strong enough in the first place ?!

[battered]

Older stuff didn't generate 150bhp and 200Nm of torque. It didn't do 60 mpg. Older stuff was heavier. Older stuff could be fixed at the side of the road with a fag packet, and older stuff NEEDED to be fixed at the side of the road with a fag packet.

Now I agree that DMFs and modern TDi's don't seem to get on too well together, but equally I'm not in a rush to go back to the days of manual advance/retard and magneto ignition.

[daytona365]

I'm not talking model T's. Just say back to a Mk5 transit or so.

[Fastdruid]

daytona365 said:

I'm not talking model T's. Just say back to a Mk5 transit or so.

The transit was pretty much the only thing that has had a SMF since the 90's! And you can tell because they sound like a bag of spanners in a washing machine. Hardly smooth.

[otolith]

JulianHJ said:

I wasn't that keen on the idea of a SMF, but the chap I spoke to seemed really keen, even though it would cost £100 less

Not always the case, though, that the cheaper priced goods have the smaller margin. Hence the keenness of some garages to sell cheap tyres.

[battered]

daytona365 said:

I'm not talking model T's. Just say back to a Mk5 transit or so.

Ah yes, that very pleasant and not at all noisy or agricultural vehicle.

We had the same arguments about elec ignition, injection, everything else. Early adopters always miss out. The fact remains that nobody wants now to go back to carbs, drum brakes on the front or any other old technology.

People forget how crap old cars were, even as recently as the mid 80's. I had a 1.4 Fiesta that never delivered as much as 40mpg. If I don't get that now off a 2L petrol I want to know why, and the thing has nearly twice the power.

[Prof Prolapse]

JulianHJ said:

Cheers, I did think that if Ford had spent millions in R&D there would be a good reason not to deviate so far from such a key component - just wanted to check as the chap at the garage was really enthusiastic about the SMF.

I think Fastdruid speaks the truth... However... You car is nearly 10 years old. How long do you intend to keep it?

I have a Ford 2.0 TDI 2005. If my DMF fails I will be changing it myself to whatever is cheaper. As it will likely be scrap or someone else problem in three years time.

[camelot1971]

I paid just over £1000 for a clutch and DMF replacement for my TDCi Mondeo at a Ford dealer last year. I made the mistake of getting Halfords to do some work on my car once - never again!

[Hasbeen]

For what it's worth, my son fitted a new genuine DMF to his 3.0L turbo diesel Ford Ranger, at about 90,000 kilometres. The old one had been increasingly rattly for a while.

When the new DMF lasted just 5 months & about 8000 kilometres, before becoming rattly, he fitted a new SMF & clutch. The replacement DMF was totally shot when removed.

There is a very slight vibration, much less than with the 5 month old replacement DMF, at low revs, if accelerating gently in high gears. You have to be really looking for it to notice. He wishes he had not wasted $1400 on the replacement DMF.

[JulianHJ]

camelot1971 said:

I paid just over £1000 for a clutch and DMF replacement for my TDCi Mondeo at a Ford dealer last year. I made the mistake of getting Halfords to do some work on my car once - never again!

If the main dealer came anywhere near the other prices, I'd seriously consider it, however Halfords have a two year guarantee, and I'll be really disappointed if I still have the car by the time that runs out. I might call the dealer tomorrow and see if they would price match Not getting my hopes up).

[spaximus]

As someone said The OE would not fit them if they were not needed, they would save a fortune if they just banged on a SMF.

What you should do before having one fitted ask them if they know how to check the DMF, to see if it needs replacing. The majority of DMF are LUK and there is a simple tool to measure deflection on the DMF. if it is within spec then it is just a clutch and cover. Some motorfactors hire this tool, but many garages just replace it all as it is good money for them and in truth they do not know how to check them. The link below shows the tool and how it works.

https://www.youtube.com/watch?v=pgBxOOTKxMI

[camelot1971]

JulianHJ said:

If the main dealer came anywhere near the other prices, I'd seriously consider it, however Halfords have a two year guarantee, and I'll be really disappointed if I still have the car by the time that runs out. I might call the dealer tomorrow and see if they would price match Not getting my hopes up).

The parts list for around £600 inc VAT from Ford so there's room for negotiations. I've used my local small town Ford dealer for the last 5 years now and they have always been competitive on price (within reason, of course).

[morgrp]

Stick the solid fly wheel on - dual mass serve one purpose in my opinion and that is to allow manufacturers to reduce the cost (and strength) of other driveline components - if you are a reasonably mechanically sympathetic driver you'll have no trouble at all running without a dual mass - 700quid to me seems a reasonable price for the work but of course it's all dependent on the model and the price of the parts

[morgrp]

Stick the solid fly wheel on - dual mass serve one purpose in my opinion and that is to allow manufacturers to reduce the cost (and strength) of other driveline components - if you are a reasonably mechanically sympathetic driver you'll have no trouble at all running without a dual mass - 700quid to me seems a reasonable price for the work but of course it's all dependent on the model and the price of the parts

[JulianHJ]

Thanks, but I think I'm going to stick with the DMF.

[lostkiwi]

The difference between an SMF and a DMF is where the shock loads are damped.
On an SMF the damping is in the clutch plate and is handled by four or six damping springs or in some cases rubber blocks. An exception to this is early minis that have no damping at all.
In a DMF the damping is performed in the flywheel and the clutch plate is solid.
Problems can arise when an SMF is used with a non damped clutch plate.
Valeo do a special DMF to SMF kit with extra long travel springs in the clutch plate.

A secondary function of a DMF is as a crankshaft vibration damper/harmonic balancer.
If you fit an SMF ideally you should fit an harmonic balancer to the crankshaft pulley end.

For the life of me I don't understand why manufacturers went down the DMF route. The SMF with a damped clutch plate and harmonic balancer worked perfectly well and was significantly more reliable than the DMF, especially for vehicles used in town/driven hard/used for towing. One common cause of DMF failure is excess heat build up in the clutch. This weakens the springs in the damping mechanism and causes premature failure.

Edited by lostkiwi on Friday 31st July 13:55

[dazwalsh]

If its done 95k on its original dmf and clutch then your doing alright, and I would replace like for like. I've got the same motor and I bet the rest of the car will fall to bits before you burn through another dmf.

[Horse Pop]

I've fitted one on my (petrol) car and it seems fine.

It's actually much more pleasant to drive.

To be fair, it's a not very torquey petrol straight six, so smooth anyway.

Diesels, I'm not so sure about. I've heard this "ooh it will snap the crank" and I suppose on a very high compression diesel engine I could see a case for this.

I can find as many people saying "Ooh it's fine" as "It will shake the gearbox to bits". This leads me to believe that doing model specific research is probably a good idea.