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Finally completed LS7 clutch install... dual mass flywheel failure.

4K views 7 replies 6 participants last post by  Oh5V 
#1 ·
After my clutch started giving me issues over a year ago, I have finally completed my LS7 clutch install.

Quick summary of my problem goes back to fall of 2010 when driving home one night, my car began to shake and the clutch pedal went to the floor. Turned out the fluid was low so I filled it back up and all was good for a few more months. Then in the spring the car had a vibration again and once again the clutch wouldn't disengage properly. I had the clutch bled by a caddy dealer and then it seemed to be ok again, but still something wrong. being that my V is not my daily driver, I kept it parked most of the time after buying the LS7 clutch setup from Lindsay Cadillac around May 2011. Right after that, I had nerve surgery on my arm which prevented doing the swap then or even driving the car for several months. However, last week I finally got around getting the old clutch out and the new one in.

In December I had changed my motor mounts seeing if that was the only cause of the vibration, It helped a bit since one mount was cracked and had leaked out, but a noticeable vibration was still there after the new mounts. At this point also, the clutch would never fully disengage and shifting was a task upon itself.

Apparently this was the first time the trans had even been out of my car(68k miles) so everything that could give me trouble by being stuck was. The dowel pins between the trans and bellhousing and between the bellhousing and engine were the worst. Since the car was in my garage and I was in no rush, I was able to let the car sit over a weeks time while i took my time with the install.

Reinstalling the LS7 parts were the easiest part. Everything went back together so much nicer. I had even bought the remote bleeder to make that task easy in the future. I even had the LS7 assembly balanced by a machine shop to prevent any new vibrations, and it turned out it was slightly off balance from GM.



With the huge dual mass flywheel and stock clutch setup finally out of the car, I inspected it for any damage or signs of the vibration cause. At first I just noticed that it had no play or rocking movement like a dual mass should. The next day is when i noticed why... The one side of the flywheel had collapsed in on itself and caused the whole flywheel on the clutch side to sit at an angle. That angle caused the vibration throughout the rpm band. and made the clutch side never fully free up. I inspected the rear main seal and input shaft of the trans and both were fine so luckily no damage was done. In the pic of the flywheel you can see the gap up top, and no gap at the bottom. I searched the web and haven't found any other examples of a dual mass failing like this.



Now that the car is running and drivable again, I can move forward with my custom projector fogs and supercharger install. :-D
 
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#5 ·
Congrats...I need to get this heavy turd out of mine as well.
 
#6 ·
Man JD03,

You got the Kooks in and you didn't remove that turd yet? I should slap you. J/K LOL!
 
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