Dual Mass Flywheel to "regular" flywheel?

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The dual mass flywheel on the Focus is warped. When engaging the clutch it seems to shake the car if it needs to slip (starting out on a hill).

The clutch material is still good. It doesn't slip at all and launches great. Pulling a pretty steep hill with the car loaded down very heavily, I was able to hold 55MPH in 3rd gear with my foot to the floor and it didn't slip at all.

The shaking is quite irritating to me. I am going to replace motor mounts in the spring to help stop transmitting the shaking through the body , but at some point, I'm going to need to have something done.

I warped the flywheel while in a traffic jam. Due to asinine gearing on this car, it idles too fast for traffic jams. Needs a stump puller granny gear. Instead of on/off the clutch (wearing it out) and riding it, I rode the brake pedal. Engine vibrated, warped flywheel.

Are there any dis/advantages to going from dual mass to single mass flywheel? It seems there are performance options and heavier duty clutches in the 'regular' single mass flywheel category.

What would be recommended to replace on it if I do this? The car has a LOT of city miles. The first 17K miles are pretty much purely city. Throwout bearing? Slave Cylinder? Any suggestions?
 
when the M/T trannie is out for servicing, it's never a bad idea to replace the throwout bearing (wear-n-tear item) and also, if possible, replace the clutch slave cylinder (OE of course) with a fresh new one.

flush the hydraulic clutch system with fresh new fluid and you'll be good for a long, long time.

Q.
 
I seriously doubt the flywheel "warped" from the scenario you describe. More likely, it broke or weakened the springs/dampers that couple the two "masses" of the flywheel- which is how dual-mass flywheels ALWAYS fail, you just accelerated the process by lugging it against the brakes.

But that's a) speculation, and b) irrelevant since what's done is done.

A dual-mass flywheels big advantage is that the whole assembly can be lighter weight than a conventional flywheel for the same vibration suppression effectiveness. Its much like a harmonic balancer, which is in effect a little dual-mass flywheel itself. A regular flywheel is certainly simpler and more tolerant of abuse, but to equal the engine smoothness and crankshaft protection you get with a dual-mass, a conventional will have to be heavier and so the engine will rev up a bit slower. Rev-matching will feel different, and there may be a performance hit if the car ever operates in an environment where the flywheel becomes the limiting factor in acceleration. Since its not an F1 or Indy car, I doubt that will happen. :) Conversely, you could equal the weight and performance, but there will be more torsional flex in the crank and more perceived roughness.

I'd probably opt for a heavier conventional flywheel if its mostly city-driven. Some day I'll face the same decision with my Challenger, but for now I try to keep it out of situations where I know the mass dampers are being rattled to the extreme.

Heres a good read:

http://www.directclutch.com.au/flywheels/dual-mass-to-solid-conversion.html

And a good animation of what goes on inside a DMF:

http://www.youtube.com/watch?v=YnaXB8q3uzQ
 
I used to have a shudder in my Saturn which would magically go away after a visit to the dealer for an oil change. I wonder if it needs a bit of burnishing? Can't hurt to try, just intentionally force a bit of slip.

At least on my Jetta SMF setups exist, and lack the notorious fault prone vw DMF. I like my SMF but it's a different car. No idea on yours. For me, everyone says it will vibrate more, and have a rumble (the DMF is supposd to smooth out vibrations) but I couldn't tell a diff.
 
I have a similar problem with my Civic (It's common). There is clutch "judder or chatter" when starting out from a dead stop and can be even worse on hills. If the vehicle is rolling even a little bit like when approaching a stop sign it wont chatter.

A little bit higher revs and slower clutch uptake will avoid the clutch chatter but makes me feel like a 16 yo. who is learning to drive a manual.

I think the problem is actually caused by NOT slipping the clutch enough to clean off deposits on the friction material and flywheel.

Bleed your clutch then drive around the neighborhood revving and slipping like a high school kid in a ricer and see if it helps clean up the clutch and flywheel.
 
Originally Posted By: Miller88

I warped the flywheel while in a traffic jam. Due to asinine gearing on this car, it idles too fast for traffic jams. Needs a stump puller granny gear. Instead of on/off the clutch (wearing it out) and riding it, I rode the brake pedal. Engine vibrated, warped flywheel.


I don't really get what you're saying here? How is idle speed related to gearing--and is the issue that you think the gearing is too high, or too low? It seems that you're implying that it needs to have a higher-ratio first gear?
 
It sounds like he wants deeper gearing. 5:1 instead of 4:1, for example. So less clutch slippage. And so it will go slower in first gear when idling along in stupid slow traffic.

My Jetta will do 5mph in first, clutch out. Any slower speed requires lots of clutch work.
 
From your youtube video, it seems you like to use the rpms below 2k quite a bit. This is where I find the DMF shines over a solid flywheel, but I guess also wears a DMF out too. Go take a 4 cylinder car for a drive with a solid flywheel and remind yourself what its like at low rpms. My Tracker grumbles and rumbles below 1800 rpm with any throttle over a tickle with its heavy single mass.
On paper the motors are similar, but the Focus motor feel much more lively, revs noticeably quicker, and smoother at all rpms.
Personally I like the ratios of the MTX75 in my Focus. 1st is low enough to get going and 5th is fine for the 55mph roads we spend 95% of our time on. You could swap one in and just don't look at the tach at higher speeds? I don't find I notice the motor anyways at 3000-3200 rpm going 70
 
Originally Posted By: Miller88

I warped the flywheel while in a traffic jam. Due to asinine gearing on this car, it idles too fast for traffic jams. Needs a stump puller granny gear. Instead of on/off the clutch (wearing it out) and riding it, I rode the brake pedal. Engine vibrated, warped flywheel.


I'd try the on/off method. Seems that would be best if you're already tearing into the clutch at 45k. I did that for years in my MT cars and clutches were fine @ 100k.
 
I replaced my OEM dual mass flywheel with a lightened single one on my Genesis Coupe. No major complaints.

I did it though because the clutch was not holding the power due to upgrades. Most of them break the springs and them make a loud clattering.
 
I had a Tiburon with a dual mass flywheel that went to [censored]. I put in a new clutch and solid chromoly flywheel, worked great.
 
Originally Posted By: JamesBond
I have a similar problem with my Civic (It's common). There is clutch "judder or chatter" when starting out from a dead stop and can be even worse on hills. If the vehicle is rolling even a little bit like when approaching a stop sign it wont chatter.

A little bit higher revs and slower clutch uptake will avoid the clutch chatter but makes me feel like a 16 yo. who is learning to drive a manual.

I think the problem is actually caused by NOT slipping the clutch enough to clean off deposits on the friction material and flywheel.

Bleed your clutch then drive around the neighborhood revving and slipping like a high school kid in a ricer and see if it helps clean up the clutch and flywheel.



This issue has been going on for 1.5 years or so. I noticed it did stop for a few months when the shifter cables had to be replaced or adjusted (can't remember) and I rode around with a ford tech. He slipped the clutch in 5 minutes more than I have ever since I got the car.

I think I'll try this first. I have figured out how to drive this car without slipping the clutch. Premium gas helps a ton, actually!


Originally Posted By: 440Magnum
I seriously doubt the flywheel "warped" from the scenario you describe. More likely, it broke or weakened the springs/dampers that couple the two "masses" of the flywheel- which is how dual-mass flywheels ALWAYS fail, you just accelerated the process by lugging it against the brakes.

But that's a) speculation, and b) irrelevant since what's done is done.

A dual-mass flywheels big advantage is that the whole assembly can be lighter weight than a conventional flywheel for the same vibration suppression effectiveness. Its much like a harmonic balancer, which is in effect a little dual-mass flywheel itself. A regular flywheel is certainly simpler and more tolerant of abuse, but to equal the engine smoothness and crankshaft protection you get with a dual-mass, a conventional will have to be heavier and so the engine will rev up a bit slower. Rev-matching will feel different, and there may be a performance hit if the car ever operates in an environment where the flywheel becomes the limiting factor in acceleration. Since its not an F1 or Indy car, I doubt that will happen. :) Conversely, you could equal the weight and performance, but there will be more torsional flex in the crank and more perceived roughness.

I'd probably opt for a heavier conventional flywheel if its mostly city-driven. Some day I'll face the same decision with my Challenger, but for now I try to keep it out of situations where I know the mass dampers are being rattled to the extreme.

Heres a good read:

http://www.directclutch.com.au/flywheels/dual-mass-to-solid-conversion.html

And a good animation of what goes on inside a DMF:

http://www.youtube.com/watch?v=YnaXB8q3uzQ



I'll have to take a look at those. Only reason I'm considering a single mass flywheel is it's cheaper.

Originally Posted By: supton
I used to have a shudder in my Saturn which would magically go away after a visit to the dealer for an oil change. I wonder if it needs a bit of burnishing? Can't hurt to try, just intentionally force a bit of slip.

At least on my Jetta SMF setups exist, and lack the notorious fault prone vw DMF. I like my SMF but it's a different car. No idea on yours. For me, everyone says it will vibrate more, and have a rumble (the DMF is supposd to smooth out vibrations) but I couldn't tell a diff.


Could be. Kind of like brake rotors pulsating when they get build ups. I've never really slipped the clutch much. Even when I was driving in the city a lot.

Originally Posted By: michaelluscher
.......your still under Powertrain warranty
Why are you doing this yourself?


Clutch issues on a manual transmission car = deny. The motor mounts I may get done under warranty ... or attempt.



Originally Posted By: itguy08
Originally Posted By: Miller88

I warped the flywheel while in a traffic jam. Due to asinine gearing on this car, it idles too fast for traffic jams. Needs a stump puller granny gear. Instead of on/off the clutch (wearing it out) and riding it, I rode the brake pedal. Engine vibrated, warped flywheel.


I'd try the on/off method. Seems that would be best if you're already tearing into the clutch at 45k. I did that for years in my MT cars and clutches were fine @ 100k.


That's what I have done previously when driving vehicles with a proper first gear.


Originally Posted By: supton
It sounds like he wants deeper gearing. 5:1 instead of 4:1, for example. So less clutch slippage. And so it will go slower in first gear when idling along in stupid slow traffic.

My Jetta will do 5mph in first, clutch out. Any slower speed requires lots of clutch work.


Exactly! Give me a 6.55:1 first gear like a SM465! Drove my father's 2001 F350 this weekend to buy an axle for the Jeep. The ZF 5 speed in that has nice gearing. Nice granny gear to get the truck rolling, then off to 2nd.
 
Originally Posted By: IndyIan
From your youtube video, it seems you like to use the rpms below 2k quite a bit. This is where I find the DMF shines over a solid flywheel, but I guess also wears a DMF out too. Go take a 4 cylinder car for a drive with a solid flywheel and remind yourself what its like at low rpms. My Tracker grumbles and rumbles below 1800 rpm with any throttle over a tickle with its heavy single mass.
On paper the motors are similar, but the Focus motor feel much more lively, revs noticeably quicker, and smoother at all rpms.
Personally I like the ratios of the MTX75 in my Focus. 1st is low enough to get going and 5th is fine for the 55mph roads we spend 95% of our time on. You could swap one in and just don't look at the tach at higher speeds? I don't find I notice the motor anyways at 3000-3200 rpm going 70


On a side note, I have been running 91 or 93 octane gas in my 2011. There is a pretty significant increase in torque under 2000RPM. Seriously. Not sure how that works.
 
I'm going to try that on my way home from work and on the way to the lake for a bike ride. This will be embarrassing and against everything I was taught when learning to drive!

I'll be wearing a hat and sunglasses
 
Hopefully the "home" rememdy works.

I think its either poor clutch design by Ford or driver error. Not a difference of Dual vs single.

I recently had the motor pulled due to valve burn from wifes 2005 Legacy turbo wagon. The mechanic as part of change out did replace the throw out bearing and cleaned up the dual mass flywheel which my wife has put 170,000 miles on. He said it was worn but not worn out. She does even drive in heavy traffic her last 5 miles of ride daily.
 
Originally Posted By: Miller88

Exactly! Give me a 6.55:1 first gear like a SM465! Drove my father's 2001 F350 this weekend to buy an axle for the Jeep. The ZF 5 speed in that has nice gearing. Nice granny gear to get the truck rolling, then off to 2nd.


Wow. Different strokes and all, but I couldn't imagine this car with even shorter gearing, and I live in a very steep, hilly are (and I've already driven this car in tons o' traffic). I don't even use 1st gear that often.

I already have my eye on a taller-geared MTX-75 from an '04 2.3L wagon. Come clutch time I'm going to swap to the lower FD ratio box.
 
Well the car doesn't shake when I rev the engine to 1200 and take off.

Originally Posted By: JOD
Originally Posted By: Miller88

Exactly! Give me a 6.55:1 first gear like a SM465! Drove my father's 2001 F350 this weekend to buy an axle for the Jeep. The ZF 5 speed in that has nice gearing. Nice granny gear to get the truck rolling, then off to 2nd.


Wow. Different strokes and all, but I couldn't imagine this car with even shorter gearing, and I live in a very steep, hilly are (and I've already driven this car in tons o' traffic). I don't even use 1st gear that often.

I already have my eye on a taller-geared MTX-75 from an '04 2.3L wagon. Come clutch time I'm going to swap to the lower FD ratio box.


They made manual trans Focus wagons? I need one!

Mine has the highest gearing from the factory in an MTX75
frown.gif
The SES model for 2011 had more "normal" gearing. It's only turning like 2500 at 75.
 
Originally Posted By: Miller88

They made manual trans Focus wagons? I need one!

Mine has the highest gearing from the factory in an MTX75
frown.gif
The SES model for 2011 had more "normal" gearing. It's only turning like 2500 at 75.


Man, they are not easy to find! I just bought a beater wagon (88 Camry) but a deal came up on a 2006 Focus wagon with a MT that I just couldn't resist.

One nice is that at least tranny swaps among these cars is pretty easy, and there are a lot of MTX-75's in junkyards for a song. I already found the tall-geared box (3.42FD) from a 2004, low miles, for cheap. I just need to pick it up. So, if you hate the gearing in your Focus, swapping it is pretty simple. If you have to pull it for a clutch job, you may as well get the gearing that you want!
 
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