Dual mass flywheel
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Drifting
Joined: Jan 2000
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From: Austin, TX, U.S.A.
Dual mass flywheel
I thought i remembered reading or hearing somewhere the car would have a dual disk clutch and a dual mass flywheel. I've only heard bad things about dual mass flywheels, so i was wondering if this was something made necessary by the vibrations created when running on 4 cylinders?
-D
-D
Le Mans Master
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From: My interests are mobile
I think this is certainly due to the fact that in 4 cyl mode, at the low cruising rpm with this tranny, they definitely used it to cancel some vibration. You'd think the deactivated cylinders would still provide counterbalance, but that must not be the case. Its unfortunate to hear about dmf, but as with anything, there always has to be compromises. They have to hit fuel mileage targets...what can they do?
The dual mass flywheels do have a problematic past in some vehicles but time has passed and the parts are getting more reliable. You cant do much but see what happens. Also, you can certainly wait until someone removes it and speaks about the characteristics after.
Not much you can do...
The dual mass flywheels do have a problematic past in some vehicles but time has passed and the parts are getting more reliable. You cant do much but see what happens. Also, you can certainly wait until someone removes it and speaks about the characteristics after.
Not much you can do...
Team Owner
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St. Jude Donor '09 thru '20
Le Mans Master
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From: My interests are mobile
Just recalling the people that would remove the dual mass flywheel from their ZF equipped c4's...man, the tranny would make all kinds of noise...like it was broke...lol. I never took the dmf out of my ZF C4, and when you shut it off it would still rattle. So...could be a tranny thing too, thats why c4's had it.
Edit: posted at same time about c4's...lol
Edit: posted at same time about c4's...lol
Le Mans Master
Joined: Dec 2006
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From: H-Town Texas
I thought i remembered reading or hearing somewhere the car would have a dual disk clutch and a dual mass flywheel. I've only heard bad things about dual mass flywheels, so i was wondering if this was something made necessary by the vibrations created when running on 4 cylinders?
-D
-D
Le Mans Master
Joined: Sep 2009
Posts: 6,937
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From: My interests are mobile
Just this little bit of talk about the C4 brings me to a good place. There's a lot of hate for the C4 out there, but you know...I loved my 92 6spd. Yeah, it wasn't a perfect car, but damn if it wasn't a descent car for the money. Great cockpit "part of the car" feel, still damn reliable (just don't wet your optispark..lol) and I drove this baby from San Diego to Pittsburgh and got 29.0mpg exactly averaged out for the trip. Freakin awesome.
Le Mans Master
Joined: Sep 2009
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From: My interests are mobile
I sure hope they addressed that hydro system, or if nothing else make the system bleedable! Good call on that! They listened to a lot of complaints of c5 and c6...i sure hope they did somethin about that.
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Racer
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The C6 is bleedable once you work out exactly where the bleeder is and get an appropriate spanner. Quite easy on a hoist but can also be done on yer back in the garage. I have done it - at least that way you bleed the entire clutch system.
Race Director
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St. Jude Donor '14
Racer
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You bleed the clutch just like any other hydraulic system without a one way valve. ie you depress the clutch whilst a second person opens the valve. At the bottom of the stroke the valve is closed and the pedal returned to the top. and the process is repeated making sure the master cylinder is kept with sufficient fluid available to prevent air getting into the system. When clean fluid comes from the bleed then the process is complete. Doing a full bleed ensures all the dirty oil is replaced with clean oil and once you work out exactly where the bleeder is, the entire process takes about 15 minutes. I explained the spanner etc in another thread.
http://forums.corvetteforum.com/1581970651-post333.html
Le Mans Master
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From: Lancaster, PA
I'm quite familiar with bleeding brakes, was wondering if a one man operations would work. Guess not.
Can I use a small wrench to open the bleeder or you need something special to "get in there"?
Can I use a small wrench to open the bleeder or you need something special to "get in there"?
Le Mans Master
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From: Lancaster, PA
Unfortunately, it is very common. When neglected it results in the clutch pedal sticking to the floor.
The slave cylinder is inside of the bellhousing exposed to clutch dust. On the release stroke the dirt sticks to the piston rod and it finds its way into the system. On the release stroke the system is not pressurized and the rod pulls in the dirt. Bad engineering design that GM never lived up to.
Drag racers will give you horror stories, I road race and the clutch does not get abused as much. Even under street use the C6 clutch fluid turns completely black in less than 6 months.
So the question remains, does the C7 improved on this?
Melting Slicks
Joined: Jun 2005
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St. Jude Donor '12-'13-'14, '16
I thought i remembered reading or hearing somewhere the car would have a dual disk clutch and a dual mass flywheel. I've only heard bad things about dual mass flywheels, so i was wondering if this was something made necessary by the vibrations created when running on 4 cylinders?
-D
-D
Last edited by DREAMERAK; Feb 4, 2013 at 03:27 PM.
Racer
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Secondly a wrench is useless - read the thread I supplied re spanner. A short 5 inch flat ring/open ended 9mm is needed on a C6 Z06 and apparently a different size on a C5. When you locate the bleeder the short ring will drop down easily onto the bleeder and once in place the rest is easy. Push toward the rear of car to unlock bleeder. But I warn you there is SFA room for hands that are less than flexible. Once you find the bleeder and use the correct spanner you can easily bleed the system in 15 minutes and that guarantees clean oil and is obviously far better than removing the transmission.
To bleed the system may be too difficult for those without dexterous mechanical ability but it is easily doable for anyone else once familiar with locations, spanner type/size, and method.
Race Director
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From: Manassas VA
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St. Jude Donor '14
Good question, but it does. This topic (dirty fluid) has been discussed in many threads. You may have seen the reference to the "Ranger" method keeping your fluid clean.
Unfortunately, it is very common. When neglected it results in the clutch pedal sticking to the floor.
The slave cylinder is inside of the bellhousing exposed to clutch dust. On the release stroke the dirt sticks to the piston rod and it finds its way into the system. On the release stroke the system is not pressurized and the rod pulls in the dirt. Bad engineering design that GM never lived up to.
Drag racers will give you horror stories, I road race and the clutch does not get abused as much. Even under street use the C6 clutch fluid turns completely black in less than 6 months.
So the question remains, does the C7 improved on this?
Unfortunately, it is very common. When neglected it results in the clutch pedal sticking to the floor.
The slave cylinder is inside of the bellhousing exposed to clutch dust. On the release stroke the dirt sticks to the piston rod and it finds its way into the system. On the release stroke the system is not pressurized and the rod pulls in the dirt. Bad engineering design that GM never lived up to.
Drag racers will give you horror stories, I road race and the clutch does not get abused as much. Even under street use the C6 clutch fluid turns completely black in less than 6 months.
So the question remains, does the C7 improved on this?
If dirt is making its way into the system then fluid has to be leaking out. Considering the pressure generated to actuate the clutch mechanism fluid would have to be squirting out to allow dust to be ingested.
I'm NOT saying the fluid isn't 'dirty', discolored..
Last edited by Bluewasp; Jan 30, 2013 at 07:12 AM.
Drifting
Joined: Feb 2005
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Dmf is a very poor tradeoff, using sheer addition of weight and rubber for a significant performance and reliability deficit to correct minor issues with noise.
Bad idea. If it is so important to have a silent car, dont buy a vette.
Bad idea. If it is so important to have a silent car, dont buy a vette.