My understanding of DMFs is that they are basically a consumable item in modern diesels. Modern diesels now produce a lot more torque than 10 years ago say and this p***s a lot of pressure on the gearbox. The DMF is there to cushion the torque spikes and thus protect the gearbox.
Some people are now replacing them with single mass flywheels and while this is fine in the short term, surely it will lead to premature gearbox failure down the line (assuming there is sound engineering behind the inclusion of DMFs in the first place).

Miks ma laagri ja hammasratastest kirjutasin, sest oli inimestel probleem kastiga. Ei väitnud, et 100% kasti viga, vaid arvustasin. Kuid inteligente ja haritud, teadaja inimene ei hakka inimest maha tegema ja leidma igasugu halvustavaid sõnu, vaid argumenteerib ja lükkab väited ümber eetika kohaselt. Siis ikka tuleb, sa oled see ja teine ja teemas arutatakse üksteise üle kel parem karvkate. Mis on selle mõte? Siis tuleb kõrgematele kasutajatele teatud teemadele lubada vastata ja nooremad ''arvustajad nn soga ajajad'' keelata. Üksteisele ära panna on ikka esirinnas veel, kahjuks! Mitu varianti sul on ukse avamiseks? Kumb, siis õige vastus on? Mitut varianti keegi pakuks?

Causes of Poor or Notchy Shifting
• Improper clutch release caused by faulty linkage or improper release linkage adjustment
• Improperly adjusted shifter or shift linkage
• Damaged/bent shift fork or forks
• Worn transmission synchronizer rings
• Improper transmission lubricant
• Pilot bearing/bushing binding on transmission input shaft
• Clutch disc hub spring pack hitting flywheel or flywheel bolts
• Damaged or defective pressure plate drive straps
• Bellhousing misalignment

Causes for Clutch Slippage
• Improper clutch adjustment
• Improper clutch release linkage adjustment
• Incorrect throwout bearing (too long or too short)
• Clutch assembly contaminated with grease or oil
• Clutch assembly not fully seated due to improper break-in procedure
• Flywheel not properly resurfaced—clutch disc is glazed
• Wrong clutch assembly for the vehicle and/or application (street, drag racing, etc.)
• Clutch assembly not strong enough for the vehicle’s power
• Broken clutch disc or missing friction material
• Defective or failed clutch assembly
• Flywheel improperly resurfaced
• Damaged or worn throwout bearing collar
• Damaged or bent clutch assembly
• Incorrect gear ratio to tire diameter

Causes of Improper Clutch Release
• Release linkage damaged, not properly adjusted or set
• Flywheel not surfaced or improperly surfaced before installing a new clutch
• Flywheel machined too thin or not manufactured to OEM specifications
• Leaking hydraulic system or trapped air in hydraulic system
• Release linkage cable stretched or damaged
• Improper clutch fork geometry due to a too-thin flywheel or deeper than stock bellhousing
• Improperly adjusted pivot ball
• Clutch disc installed backwards
• Clutch disc hitting flywheel bolts
• Clutch disc binding on transmission input shaft
• Clutch disc runout due to bent input shaft
• Bent or damaged pressure plate assembly and/or clutch disc
• Clutch disc is too thick or has an excessive marcel spring
• Pressure plate has defective or damaged drive straps
• Damaged, worn, or improperly installed pivot bearing/bushing
• Damaged or worn throwout bearing collar

Causes of Clutch Chatter or Shudder
• Improper break-in procedure
• Flywheel not properly resurfaced before installing a new clutch
• Flywheel or clutch disc friction surface not parallel with the crank flange surface
• Flywheel has severe hard spots or hot spots
• Flywheel has an improper step or cup dimension
• Defective pressure plate and/or disc
• Disc has inadequate or no marcel (not enough cushion between friction facings)
• Oil or grease contamination on clutch facings
• Worn or damaged clutch linkage
• Bent cover assembly and/or clutch disc
• Damaged/excessively worn U-joints or CV joints
• Misaligned U-joints
• Excessive backlash in differential
• Excessive driveline angle
• Improper gear ratio versus tire diameter
• Improperly tuned engine
• Worn/damaged engine or transmission mounts
• Bad leaf springs, bushings or mounts