CLUTCH TECH: Dual-Mass and Single-Mass Flywheel Information

Dual-mass flywheels are an increasingly common component of modern clutch systems. Today on Clutch Tech we look at how a dual mass flywheel works, why they are used and the common Single-mass conversion.

[@TheBalrog111]

Thank you for the information.

[@AndyMarcelin]

Thank you !

[@ouimetco]

Really good info

[@KevW03]

Very useful video

[@likesurfs]

I love single mass flawel

[@damnun]

I like your joke

[@stevensilz-carson1793]

I switched my 2012 VW 2.0L (gas) Turbo's OEM dual mass clutch (210 ft lb at crank) , which the previous owner had basically cooked in 25K miles. Instead, I placed a SPEC brand (Stage 1) 17 lb steel, single mass flywheel with sprung, "organic" disc. Everything is strong now and feels as it should --- except for-the-in-neutral-off-the-pedal racket from the gearbox spinning with less damping. No grinding of synchros, easy shifting, too. Do you think it's worth dumping in some extra high viscosity gearbox oil in to help dampen out the "cement mixer" sound effects when idling in neutral? BTW, the moment I apply pressure to the clutch pedal, the noise stops completely. Or might you have any other thoughts on resolving the matter? Steven in Colorado

[@Alexander_l322]

My DMF has been a DMF too long so it isn’t doing it’s job anymore. The noise on idle from I suspect to be the gearbox is like a blender full of nails and it tends to slip under acceleration and up hills. I can’t use first gear because it just jumps out, bangs loudly and grinds when I try to pull off so I’ve been using second gear to get moving which isn’t great on a hill because I have to slip the clutch to stop it from stalling. What can I expect if I changed to a SMF and new clutch kit in terms of the noise being louder or quieter and drivability of the car after installing the SMF? I mean it’s bad now but still drivable and quiet once it’s going down the road.

[@Rockafella]

Thanks, informative. Will I need to use different gearbox oil going from a dual mass to single mass flywheel?

[@australianclutchservices7503]

Hi Stefan, Glad this was helpful for you. You do not need to change the type of gearbox oil when changing from a dual mass to single mass flywheel. If we can help any further, please feel free to email us at [e-mail] and our friendly sales team will help guide you. Thanks

[@Rockafella]

Thanks for the reply guys! :)

[@birdonfirefitnesspt]

Thanks for the video guys. I have a failing clutch in my 2013 T31 Nissan Xtrail (63,000 kms). I'm reluctant to replace with another DMF as I've heard they are substandard for this vehicle. Would you recommend an SMF conversion, even though I mostly do city driving? TIA

[@australianclutchservices7503]

Hi and sorry for the late response. These are a popular conversion and we offer both the standard replacement with the dual mass and a single mass conversion. It is important to remember the side effects of a single mass conversion as discussed in the video, mainly being the increase in Noise, Vibration and Harshness (NVH). It is more expensive to purchase a dual mass flywheel but it does come down to personal preference and what you are looking for in the vehicle. If you would like any further information, please feel free to contact our friendly sales team on 1800 CLUTCH (Within Australia) or email [e-mail]

[@jasonstrong4610]

its now 3 years later. my 09 T31 now has a deceased clutch. i had no idea dual mass was useless for towing heavy loads in my 3m tandem trailer. after all, the manual drive is good for 2 ton right? i very much doubt it. it will be the last x trail i buy. digital gauge for temperature etc is too small to read for an older guy. the front end was designed by satan. and moving stick forward to select reverse is stupid.

[@Alexander_l322]

@@jasonstrong4610 why the hell did you buy one in the first place lol

[@radioman321]

I’m late to the video, but I’m curious about off road low end torque. I’m haven’t increased power, but I use this SUV rarely around town. It’s primarily used off road and occasionally for towing. 1. Would a SMF be more suitable for me? 2. Why specifically would the SMF (or DMF) be more suitable off road?

[@TheJessefuji]

Love a good flywool

[@032254855]

getting a stage 2 tune on my defender will do about 200hp and around 400nm of torque after the tune. The guy's doing the tune recommended i put a heavy clutch in and a single mass flywheel in i don't do a lot of towing but do a bit of off roading do you think the single mass flywheel is the way to go

[@australianclutchservices7503]

Hi Roza, If you are installing a heavy duty clutch, the Single Mass Flywheel conversion is a popular modification to complete at the same time. Nearly all of our heavy duty kits come with a single mass flywheel conversion when being used in an application that had a dual mass from factory. An SMF conversion can result in increased noise, vibration and harmonics but if you would like to learn more about this conversion in your specific vehicle, please email [e-mail] and one of our friendly sales team will be able to advise you further. Thanks

[@omarabdelaziz-el-ashry-Eg]

Hello, I get heavy slapping when kickdown. Do you think this come from flywheel? There is no noise coming from flywheel. It's Automatica transmission. What do you say about this?

[@australianclutchservices7503]

Hi, As this is an automatic transmission, we would recommend you take this vehicle to a local mechanic or specialist to help identify this noise. Thanks

[@flaskandsarnies]

Its probably important to think why the manufacturer went to the trouble of fitting a more complex and expensive dmf. Clutches and flywheels are consumables, uprating power or towing a cattle truck out of a ditch wont help any clutch or flywheel, its just a matter of how much money you have to spend on repairs...

[@David-lr2vi]

flaskandsarnies. I can think of one good reason the manufacturers put DMFs into cars. So they can rip people off when it’s time to replace them! Cars only had SMFs for over 100 years and most flywheels never needed replacing for the life of the vehicle and now all of a sudden cars can’t do without disposable DMFs? I don’t think so. At the end of the day car manufacturers are in the business of selling new cars. If a car manufacturer can introduce something like a DMF that makes a car smoother to drive to help get the new car sale and it will reasonably last out the warranty period they will do it. Longevity of service is none of their concern because people who buy new cars don’t care about longevity past the warranty period as they predominantly don’t keep the same car for 10-20 years, they buy a new one 2 or 3 years later or when the warranty is about to expire! The impression on the potential new car buyer when they are driving the demo to make a decision on which car they buy means everything to the car manufacturer as this is their sole goal, to sell more cars. If they can also make the replacement part hideously expensive to replace then that’s also a win for them!

[@user-ye9ov8cu3t]

Where do you guys supply the torque setting for the bolts these days?..

[@australianclutchservices7503]

Hi, We list the flywheel bolt torque on our online catalogue against the flywheel itself (where available). This catalogue is available at www.australianclutch.com.au/catalogue/auto-catalogue We also list the available specs on the label of the bag the bolts are provided in. Thanks

[@upupandaway5646]

I'm going to a single mass on my 2006 jetta tdi is that safe

[@tysonredbear2085]

I kept thinking you were talking about flow 🧐😅

[@senscherbakoff4686]

Hi there i have an Audi a5 3.0 tdi Quattro. I have an excessive vibration in the cabin of the car. I took it to one garage and they told me all i need to do is change the engine mounts, i also took it to another garage and they said not only do i have to change the engine mounts but i have to change the dual mass fly wheel as well. When i turn the ac on, the car revs goes from 610 to 910 and the vibrations stops completely until the ac is turned off again. Do you think this could be a problem with the dual mass fly wheel. Many thanks !!!!!! Please get back to me asap before i waste a lot of money !! P.S the engine sounds completely the same when i engage and dis engage the clutch.

[@australianclutchservices7503]

Hi Sen, Dual mass flywheels can cause vibration in the vehicle when they fail, however the AC side of things does not indicate a typical dual mass flywheel failure, although it is possible. It is very difficult to tell without inspecting the vehicle. I would suggest you have the vehicle inspected by a dealer or specialist. Thanks

[@sanderk95]

Your air conditioning runs with a belt to a pulley which is connected to your engine (V-belt) same as your alterntor and waterpump if this engine has it outside the block , so yes it could be possible since your engine has a little more ressistance on the power delivering end or keep the Rpm beneath the stock stationairy Rpm wich could cause vibrations on the Shaft that connects your gearbox to your engine

[@SamVieiraGuitar]

What do you mean single mass flowel, dual mass flowel?

[@australianclutchservices7503]

Hi Sam, These are two different types of flywheels commonly found in production cars. The video explains the key differences but the Dual-mass flywheel allows for improved dampening characteristics over a traditional single-mass flywheel.

[@ronvelasco9530]

What is the best brand of single mass flywheel for 2003 BMW 325i E46?

[@australianclutchservices7503]

Hi, We offer a range of high quality single-mass flywheel conversions for this vehicle including both standard replacement clutch kits with a single -mass conversion flywheel and also a performance upgrade clutch with a chromoly performance single-mass flywheel. If you could please email our sales team at [e-mail] with some further details on the vehicle such as performance modifications made and what it is used for, they will be able to assist you with a kit to suit. Thanks

[@davidhouk7454]

Flywheel or flyall

[@veka9405]

If you can drive don't need a dual massage flywheel I converted and not much of a difference you got to put up more rpm for initial take off

[@agt155]

The dual-mass flywheel is there to save your gearbox.

[@veka9405]

The difference is unnoticeable

[@veka9405]

Technology is there just to pull more money out of your pocket

[@veka9405]

Single massage with outer slave cylinder lasted for years now inner slave is more labor and 4 times the cost of clutch

[@agt155]

@@veka9405 Your transmission will wear out more quickly without a dual-mass flywheel protecting it.

[@agt155]

The dual mass flywheel is there to dampen torque pulses from the engine. Remove at your peril.

[@MrLunithy]

Don't go to single from dual in 2020.

[@thestigseuropeancousin7941]

Wtf is a flawell?

[@danielhertz7266]

Bull shite. The dmf is about making money and nothing to do with vibration bs. That has everything to do with poor design balancing/ firing order etc. They make the dual mass flywheels to fail.

[@15sixmedia]

Flahwall

[@e90_austin]

“Flahwuhl”

[@SirUncleCid]

flawul

[@31acruz]

You forgot to list the biggest benefit of the dual mass flywheel: They hold the rpm's while you take your time shifting. That alone is worth GOLD, I would never convert to single mass, would be like raping my BMW E36 M3, screw that.

[@YGDification]

THE SMF IS WHY BETTER BRO !THE SMF HAS NO DEATH!THE DMF IS GOING TO FALL EVERY 80.000-150.000 KM (AND IS NOT CHEAP TO REPLACE!) !😉