DMF failure symptoms?

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Citroenmad
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DMF failure symptoms?

Post by Citroenmad » 05 Sep 2010, 20:58

What are the first stages of the DMF failing? I think mine might be on its way out, or the gearbox is :(

Recently the gears have become stiffer, especially getting into 2nd where its very notchy and often crunches. However now 4th is crunching regularily and is also notchy.

The clutch is starting to judder when pulling away and the bite possibly seems higher.

Ive not heard anything too drastic about gearboxes on these, so im asuming its something else. Though it does appear to be as if the syncro-mesh is weak.

The gearbos oil was changed two weeks ago when the cambelt got done. It started getting a bit crunchy and hard to change gear about 6 weeks ago, but its getting worse.

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myglaren
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DMF failure symptoms?

Post by myglaren » 05 Sep 2010, 23:16

Could be clutch failure or possibly the hydraulic clutch operating mechanism could need bleeding - or has a leak.

Citroenmad
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DMF failure symptoms?

Post by Citroenmad » 05 Sep 2010, 23:25

I think bleeding the system will be my first job and checking for leaks. Though with its recent fuel leak its hard to see whats leaking and what isn't.

At the moment im less than impressed with C5s, why are they not more like Xantias and Xms. :roll:

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DMF failure symptoms?

Post by RichardW » 06 Sep 2010, 08:00

You would appear to be suffering classic clutch failure symptoms, but it could be a fault with the relase mechanism. Failure of the DMF will (should?) not result in difficulty in selecting gears (well not till it it disintegrates totally and makes a bid for freedom out the bell housing!). As the DMF is part of the clutch, it should be checked for excessive play at the time of clutch replacement and replaced as required. If the DMF is on the way out then possible symptoms include a squeak on taking up drive, a squeak on engine shutdown, and possibly judder on drive take up.

KP
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DMF failure symptoms?

Post by KP » 06 Sep 2010, 08:47

is this not one of the C5's that uses the same HDI engine as in the Xantias so thus it can be replaced easily with a solid flyhweel and proper clutch arrangement for not too much money?

It too sounds to me like the clutch is on its way out but agree that it also sounds like a snychromesh issue on the gearbox.

has the car ever had a hard time in life pulling very heavey loads for a long time or such like maybe causing the gearbox to overheat?

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DMF failure symptoms?

Post by Citroenmad » 06 Sep 2010, 19:50

To my knowledge its had a good life, it didnt (until last week) have a tow bar fitted so it wont have pulled any heavy loads. I got it fitted to take the bike rack.

Ive had the gearbox oil changed, which has made changes a little smoother but its still crunching. The gears can always be selected, 2nd is sometimes a bit stiff but its the crunching which concerns me. It started on 2nd gear, but now 4th is worse. Only 2nd and 4th crunch but its notchy.

Our 52reg C5 has a solid flywheel, so far its lasted longer than its original DMF which did 60K miles.

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DMF failure symptoms?

Post by Deanxm » 06 Sep 2010, 20:02

Hi Chris

just sounds like the clutch isnt disingaging fully to me, there is no way the gearbox is going on a car that new unless you have been abusing it.

DMF just flaps around if it packs in and makes takeoff juddery as has been mentioned.

D

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DMF failure symptoms?

Post by Citroenmad » 06 Sep 2010, 20:11

I hope its not the gearbox which is going, its not a problem with C5s. Ive not been abusing the box, so hopefully that is ok.

I think my first port of call will be to bleed to the clutch and see how it goes from there.

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DMF failure symptoms?

Post by Deanxm » 06 Sep 2010, 20:13

is the bite point really low?

Citroenmad
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DMF failure symptoms?

Post by Citroenmad » 06 Sep 2010, 20:15

No, the bite point seems about right, if anything its a little higher than it used to be.

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DMF failure symptoms?

Post by Deanxm » 06 Sep 2010, 20:21

wouldnt of thought the clutch is dragging then if the bite point isnt low, to be honest i have no idea then, after that i would say worn syncro's but on all gears? seems unlikely somehow, usualy they only fail on second after many many miles.

D

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DMF failure symptoms?

Post by Citroenmad » 06 Sep 2010, 20:27

Well the previous owner changed it for an automatic, maybe that has somehting to do with it!

Im at a loss too, ill ask the citroen indy this week, see what he suggests