I'm really thinking I need a clutch replacement, I'm at 90k miles and the clutch has a decent chatter to it. Still driveable, but annoying. I'm going to drop the transmission to replace the overdrive unit anyway, so I figure might as well do the clutch at the same time.

The shop is telling me that they have to resurface or replace the flywheel when replacing the clutch, or it will chatter even with the new clutch. Is this true? I thought you can't resurface a dual mass flywheel?

Looking on Rockauto, there are a couple replacement options for the flywheel. I am looking at the LUK replacement as I am most likely going to get a LUK clutch kit anyway, and it's not expensive. I can't tell if it is a dual mass flywheel or not, though (I know that you can convert to single mass but I'm thinking I don't want to do that). Here is the link: https://www.rockauto.com/en/moreinfo...041208&jsn=475

Can you guys help me understand what I need to do here? Thank you!

 

Hello again, Bfenty
I had that predicament with one of my German cars that came equipped with the Dual Mass Flywheel and Clutch and they told me how much it cost to replace it I was shocked! The difference was big money back then and I went straight to the standard type clutch and never had any issues. The Dual mass flywheels can't be fixed, re-surfaced or even rebuilt without spending a lot of money. I can't feel the difference when I drive the car, so why all the money?

Deviation:
(My youngest was heading back to school and started hinting about cars, specifically a 2011 Camaro, "Bright Yellow" with a 6 speed with the "little" six cylinder (3.6 liter DOHC ((312)) hp engine). She sold her Mom on the fact it was "just a 6 cylinder" and the six speed would allow her to get some mileage.... 19 years old studying to be an Aerospace Engineer in Florida and I am sure that she drove the 800 miles laughing the whole way.) Kids... Were our parents so gullible?

That "Camaro" came with the dreaded "Dual Mass" type Flywheel and Clutch, several mechanics have warned me that to replace the Camaro Factory clutch will cost between $3500-4000, I will remove it and install a standard flywheel and old fashioned clutch. I am sure that others feel differently but to me it just is not worth the extra money involved. That is the opinion of a "Former Dual-Mass Flywheel" person for all it is worth. I found that after driving her six speed that I actually like driving my old four speed Corvette. I guess I am getting old.

Good luck my friend and I hope that Corvette of your doesn't break the bank on you. Whatever happened to a $400 clutch replacement like the "old" days? $39.99 for a tune up with plugs, points, cap and rotor... I am old.

 

 

For 60 bucks, it's solid..

A search on the part says it's solid:

https://www.carid.com/luk/flywheel-mpn-lfw131.html

I know some people swear by them, but I've never owned a car with a DMF flywheel and they all worked just fine.

In fact, a bunch of the Ford trucks had the DMF and we pitch them in favor of the SMF and they all work just fine.

One of the big things about installing a clutch is not to hang the trans from the disk during installation. If you do and you bend the disk, they will all chatter regardless of brand, smf/dmf, or anything else.

LUK products are really good quality, btw. It's probably a good pick..

Here's a catalog with the rest of the parts if you need it.
http://www.manualtransmissionpart.co...2015-16_us.pdf

 

 

 

If I had the trans out anyway I would because I hate to revisit things.. But if it works properly it isn't absolutely necessary.

 

 

Other people will disagree with me.. But I would lose any DMF setup on the car.

I would use the LUK kit and flywheel. The quality is good. It will work fine for a stockish C4.

I have removed many 225-250K Luk and Valeo clutches from diesel trucks here because the pilot or TO bearing failed, but the clutch itself was in remarkably good shape.

If the car were mine, that is what I would do. Other people will have their own opinion.

 

PS: I have installed many single, and even dual, disk SMF setups here.. They all worked fine.

I have never had a customer request a DMF to be rebuilt or replaced with another.

 

Wait, what year is your car? It sounds like you have the 4+3 transmission and not the later ZF6, right? If so, then I don't think your original flywheel was a dual-mass unit. The DM flywheel was used for the ZF6 transmission to quell the rattle it makes at idle/neutral. You can replace with a SMF (and the DMs are hard to find now), and everything runs and works properly. It's just that the rattle noise appears. But anyway, I don't think you have to worry because yours should be a solid flywheel and the OE disk should have a sprung hub. The flywheel you linked to at RockAuto is also a solid (single-mass) unit.

To answer the question in the OP, it's recommended to either resurface or replace the flywheel. The DM flywheels are supposed to be difficult to resurface, but a solid one should be no problem (as long as it's not warped or otherwise jacked up).

 

 

Yeah, I do own a transmission shop.. BUT, in fairness and honesty, this is an AG area and I have only serviced one (1) C4 in 15 years besides my own.

I just don't see them? Mostly trucks and SUV's. So, there's that.

But I think MM hit it right on the money, because when I look through the LUK catalog for the FW part number, I see it also fitting cars back into the 70's, and those would be SMF.

So your FW may be fine. If itt's in good shape you can just use it.

 

 

Sadly, I've never seen one. I looked at a couple of used ones on Ebay, and they appear to be SMF also. I bet it's SMF like MM says.



If not, when you pull it apart, a DMF is easy to spot. They weigh approximately 10 billion pounds and the center is sprung.

 

With 120 views I would have thought someone who swapped a clutch would chime in by now?

 

If it's a 1985 C4 with 4+3 it's a SMF. I don't see a conversion kit actually listed at RA for one, and every actual replacement flywheel they sell is a SMF. The 4+3 transmission is just a Borg Warner Super T-10 with the Nash overdrive unit added to the tailshaft. The T-10 goes back to the early 70s or maybe even the 60s, and never needed a DMF.

BTW, the flywheels at RA are very cheap: $52-$75 for a brand new one. If your original flywheel turns out to need surfacing or be out of spec, I doubt I'd even bother trying to have it machined. For that price, I'd just replace it.

 

Not seeing any of that in the LUK catalog. 04-080 is listed as a clutch kit. It looks like a stock replacement. Application notes don't mention a conversion from DMF to SMF. FW Part number doesn't mention a conversion.

I think it's an SMF and you can just buy the 04-080 and it will be fine. You can find it on page 45 of the LUK catalog.