1.6hdi clutch flywheel or solid ??

[white exec]

Wonder what they mean by "low inertia disc"? Surely not the tiny reduction in mass of the friction plate?
Or are they referring to the flywheel itself?

You've been lucky with DMFs. I haven't.
RAV4 first one lasted 60k mi, and its 'improved' genuine Toyota replacement lasted another 24k mi. Both shredded their friction plates as the flywheels developed rotational slop. And we drive gently, having never worn out a clutch since starting driving somewhere about the middle of the last century.

Modern clutchplate material really doesn't help. Resin+glassfibre string is no durability-substitute for the old asbestos compound, although obviously the latter is gladly gone. Wonder what the military use?

[myglaren]

My first one - in the estate - was changed along with the clutch at about 130,000 miles due to a mis-diagnosis - the fault was an injector.
While it was still working OK it was near the end of it's life.
Current one seems OK at >211,000 miles of much abuse.

[aneesh84]

I don't think that DMF's are flawed in concept, and in my experience can run fine for high mileages (the one on my wife's car has done 240,000 km, and the one in my Fiat was fine at 120,000 miles when the clutch release bearing went) but they probably do need treating with respect.

Can you explain what you mean by "treating with respect". Does it mean avoiding low rev driving?

[Bob L'eponge]

Can you explain what you mean by "treating with respect". Does it mean avoiding low rev driving?

From what I have seen the main thing is to avoid over-heating the clutch (for example by riding it) as this damages the rubber buffers inside the flywheel.

[white exec]

Sometimes easier said than done. Many vehicles now have quite a high reverse gear (compared to 20+ years ago), and this has been noted as making hill-starts in reverse quite difficult without higher engine revs and wear on the clutch. Couple this with the relative delicacy of modern clutch linings, and throw in a less-than-new DMF, and it is all too easy to overheat a clutch, even in expert hands. The appalling smell of burnt resin is the instant giveaway.

If you unlucky enough to have a sloping driveway, which you need to reverse up, then this doesn't help.

[jsp]

HDI have short gearing 1st and reverse to compensate it.

[Romzi]

It's not so much that the manufacturers look to sell engines that are 'harsher', rather DMF's have been a response to the increased peak torque values that a modern common-rail diesel engine can produce. (Which I suppose could be seen to be the same thing, although most would see a 'harsh' engine as being a negative thing, but increased torque as being a positive.)

I don't think that DMF's are flawed in concept, and in my experience can run fine for high mileages (the one on my wife's car has done 240,000 km, and the one in my Fiat was fine at 120,000 miles when the clutch release bearing went) but they probably do need treating with respect.

So basically, we get this high torque engine which requires DMF, but are not alloweed to use that torque to prevent damagaing DMF. This is ridiculous.
Sorry Bob, it's not your fault, I'm just reading this sort of contradictionary info over and over again....

Now about me.... Citroen C5 break, MK2, year 2004, 2.0 HDI.
The complete clutch was replaced 4 years ago (Luk DMF repset).
Just out of clutch warranty (1 year) , after only a little bit over 20.000 km (not miles!), the clutch began to slip.
Sometimes, it was slipping, sometimes not. It was worse in winter, and better in summer, but in all this time, it was getting oin my nervers.
The engine is not remapped, or nothing else is changed. I do tow our caravan occasionally (900 kg), but....
This is why I bought this (high peak torque diesel powered) car in the first place.
But I am not heavy user, also the caravan is way beyond alowed towing weight for this car.
Anyway, now, after about 100.000 km, these crappy clutch is finished. It's slipping all the time.
Are there any cons about Valeo 4p kit, except a little more noise and vibrations from the engine?
And, If somene knows: is there eny info about max Torque, thid clutch can withstand?
BTW, this HDI does not like driving in low end revs, it gets normally useful and alive at about 1800-2000 rpm, so what's the point using DMF anyway?
My VIN is: VF7**************[VIN obfuscated, can be read by forum staff]
If i am correct, the right kit for my car is Valeo 835068.

[white exec]

I went through two DMFs on our RAV4 2.0 D4D, both genuine Toyota, the second one "improved". One lasted 60k km, the second just 24k km. Both developed massive backlash, broke up, and destroyed their friction plates.

Car now has a Blueprint 4p kit (Valeo one not available) and has run from 80k to 220k km without issue. Hill starts and reverse hills never simpler, and achievable without the need to over-rev. Worked for me, but then not a C5.

Only difference in friction plates is that DMF ones are unsprung (plain centre), while SMF ones contain the conventional short springs.

[Romzi]

Thanks.
I would really like to read some impression (review) from someone with the same car (or similar car with the same engine and transmission, like P 407). I read some horror stories about broken shafts and so on, but never from the owner directly.

[white exec]

Lots of rumours about broken bits, but rarely any first-hand/verified reports, as you say.

One interesting question is whether the same engine and output shafting was ever produced with SMF as standard (the RAV4's D4D was) for other models, which ought to indicate that its design around a conventional flywheel was sound.

In your position, the choice is another DMF or an SMF 4p conversion (far less expensive), and I think I would be going for the latter. If it turned out that it wasn't good enough - eg unacceptable vibration - then another DMF would always remain an option, and the lost cost wouldn't have been too bad.

Valeo produce some well-renowned components, and they chose long ago to produce and market SMF alternative (4p) kits for all sorts of makes, and have continued to do this for some years. (One of theirs wasn't available for Toyota D4Ds 'for commercial reasons'; it seemed this was because they were supplying Toyota with OE DMF equipment, and so couldn't also offer an alternative.)

[GiveMeABreak]

Don't ignore the possibility of a crankshaft oil seal failure - that happened to me after changing the clutch and DMF after slipping (DMF was badly worn - previous owner towed with the C5 X7). Then about 16k miles later slipping started again - took it back and the oil from the crank seal has leaked onto the clutch and contaminated the friction plates - had the seal done and the clutch replaced and has been fine since.

There is no data on the max. torque that the clutches take - but I can tell you they are different for the various engines and whether they have DPFs or not and ditto for the DMFs - so would have different tolerances based on that alone I suspect.

[white exec]

Towing - yes - DMF pretty much unsuited to full-sized towing, so another reason to call it a day.
Too much "wind up", and poorer clutch control - especially in reverse or on a hill; just what you don't need.

[Romzi]

Don't ignore the possibility of a crankshaft oil seal failure - that happened to me after changing the clutch and DMF after slipping (DMF was badly worn - previous owner towed with the C5 X7).

I am quite sure, it was replaced last time the clutch was replaced.
Now, slipage is getting worse almost every day.
Will get back to report what I have decided and make some short review if i will go SMF path..

[Romzi]

I've got some info from the dealers in Slovenia, and mostly opinion is, Valeo 4p for this setup is no-go.
I am more and more sure we will use new OEM DMF plus Sachs Performance Clutch kit (https://www.sachsperformance.com/en/clu ... 00951837-s).
It is quite reliable solution, but quite expensive.
Are there any delaers fro this, or only online buy from above webpage?

[aneesh84]

I've got some info from the dealers in Slovenia, and mostly opinion is, Valeo 4p for this setup is no-go.
I am more and more sure we will use new OEM DMF plus Sachs Performance Clutch kit (https://www.sachsperformance.com/en/clu ... 00951837-s).
It is quite reliable solution, but quite expensive.
Are there any delaers fro this, or only online buy from above webpage?

What are the reported problems with valeo 4p? I generally had heard of good feedback about them.