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DMF to Solid/Rigid Mass Flywheel

Why DMF or SMF

June 4, 2020

This is a guide for people looking to convert their current DMF dual mass flywheels to solid (normal) type flywheels. You are looking at this guide because your car needs its dual mass flywheel replaced and are considering having it replaced with a solid flywheel conversion kit.

This post will help to avoide false claims by certain 'I don't believe in changing things because the manufacturer must have put it there for a good reason' type people.

The claims of the DMF flywheel are that it helps to reduce engine vibrations and vibrations heading to the transmission of the vehicle.
These claims are not false, however, a solid mass flywheel with the correct SPRING CLUTCH PLATE DOES THE EXACT SAME JOB.
Manufacturers and designers of the DMF don't ever mention that a standard type flywheel and clutch (solid) has damping properties and concentrate on telling the public how the DMF does such a good job.
I personally hate it when they don't compare the design with existing designs which also work - and are much simpler to produce and are more cost effective.
The only difference is a solid flywheel clutch doesn't damp at the same rate and has a far lower failure rate. This doesn't mean you will be destroying the gearbox by doing the conversion, it means you MIGHT get a little more engine noise if you like driving in super low RPM and doing hard engine pulls from low RPM's. This is the reason why DMF's failed - a solid one will not fail because of this and it will most certainly last a lot longer.

When your DMF fails you run the risk of clutch failure.
When a solid flywheel fails - wait - SOLID FLYWHEELS DON'T FAIL. They can burn out if your clutch fails, but that's the same for the DMF.
Advantage - Solid flywheel.

Some people will change their DMF for a solid one only to be stung by the cost of the clutch plate. Do the math first, please.
If you plan to keep the car for over 5 years and you are at the point of replacing your DMF, I would consider the conversion seriously.
A lot of people selling the SMF will make a massive markup on the clutch plate simply to make up more profit for not selling a DMF so shop around - if the price is good enough, buy 2 plates so you are good for at least the next clutch replacement!

If you are considering welding the DMF so it no longer has play, DON'T, UNLESS - you change the clutch plate for the spring type found in the solid flywheel.
This will essentially convert your DMF to a solid with the welds. Please get your welded flywheel balanced before you refit to avoid the characteristic juddering on idle and high RPM.

Always check the release bearings are in good condition, and if you have the hydraulic release bearing, please install it in the compressed position to avoid failure when re-fitting and bleed it once the gearbox is bolted to the engine.
I have seen people who have replaced their DMFs with solid and then complain about a rumble when the car is idling and the noise goes away when the clutch is pressed. Classic mistake of neglecting a small part in the path of saving money.

Always use a garage with a good rep and are always busy. A sign of a bad garage is - they will be eager to book you in today and will not have a waiting period to get the work started. (This is general, sometimes, SOMETIMES, good garages will be able to accomodate customers quickly if they have a big enough garage and mechanics.)

Zndmotor is professional on the DMF conversion--solid mass flywheel since 2008. Now we are successful on the Mitsubishi 4M41, Nissan Navarra, Ford transit, VW, Audi, Peugeot DMF flywheel.

Any questions are welcome.