WardVette

I bought a Spec 3 clutch and steel flywheel from a forum member several months back. He said it was new in the box, but when I got the setup it had been taken out and then put back. It was a little dirty but I didn't think it had been installed. I finally got it installed at the dealership 2 days ago (along with a new torque tube), and now my car vibrates horribly. It is the worst under acceleration at high rpms in first, but it even vibrates at idle and revving with the clutch in or out. This makes me believe something is out balance in front of the clutch. So either something in my motor is bent (unlikely) or my flywheel or pressure plate is warped or out of balance. It was vibrating before I took it in, but I assumed it was the torque tube. The vibration is worse now. Is there anything else that could be causing this? Do I have any other options? If I have to buy another clutch and flywheel and have it installed, I'll be over $3500 (and the torque tube was discounted to only $575 since my dad gets wholesale). What a nightmare.

VetteDrmr

Owww. I hate to say it, but I think you've got the right analysis; it's either the flywheel or PP. I did a clutch R&R on my '94 Z-28 and had exactly the same symptoms as you describe. I bet the magnitude of the vibration changes with engine rpm, too.

Mine was tracked down to a botch job by the machine shop that resurfaced the flywheel; they had originally machined in a 0.011" tilt across the entire surface!

It could be an install problem, don't let the dealer off the hook completely.

Hate to be the bearer (or confirmer) of bad news, but hang in there.

Mike

dudleyd

[QUOTE=WardVette] It was vibrating before I took it in, but I assumed it was the torque tube. The vibration is worse now. QUOTE]

Check the Harmonic ballancer at the front of the motor, make sure it's not wobbling and coming apart.

WardVette

I was wondering if the harmonic balancer could be bad. Would a bad torque tube cause the h balancer to go bad if I drove it a while?

Ikester

Sometimes the new flywheel needs to be balanced to the stock one. If you dont you will get vibrations. Hopefully the mechanic knew that.

dudleyd

I'm not to sure about a bad torque tube throwing out the balancer, but I'm not saying it couldn't happen. If the harmonic balancer is bad it's prity obvious as it will have a wobble in it and can ultimately come completly seperated It is a fairly common problem on the LSx motor. So how did you come to the conculsion that the torque tube was bad?

WardVette

It clunked and sqeeled horribly. They showed me the old tube and the coupler was gone.

SteveDoten

new pilot bearing by the dealer, yes? if the coupler was gone, most likely the pilot bearing is the same

i doubt they would skimp on a $10 part

SpinMonster

You were a bit unclear if the car vibrates while standing still and revving it. The motor only spins with the flywheel and pressure plate wile standing still. The drive axle in the TTube isnt spinning at that point. If there is no vibration when you rev it standing still, its after the TT ( may be further back too, don't limit the search to the TT). If it vibrates when revving and standing still then the clutch assembly could be out of balance and I would ask if you had it balanced as an assembly prior to installing. If the dealer didnt ask you about the balance then I would ask them why they didnt balance the assmebly. Sounds to me like you skipped a step and didnt balance it.

I have yet to find a clutch assembly that was properly balanced from the factory. That includes my SPEC 3 which was out but not as far as my RAM was.

dudleyd

My LS7 clutch assy was zerro ballanced from the factory. NO ballancing required and it is runs smoth as silk.

WardVette

I didn't ask them to balance it. I figured they would do it if it needed to be done. Maybe that's the problem. Are you sure it has to be balanced? Seems like there are different opinions on this. It vibrates while sitting still at idle and when revving. This is with or without the clutch in.

Fastguy

Ls1's are very balance sensitive. If they are out even a little, they will vibrate. If the balancer is good and the torque tube is too, its probably the clutch /pp/FW assembly. You can drop the inspection cover and add washers to the PP bolts to try to get it to go away or you can pull the whole mess and have it re-balanced. My Spec III was way out when I brought it to a machine shop.

Blowndave

i installed a z06 clutch and flywheel assy direct from gm and i had the same problem as you did. i completely had to remove it and exchange it for another unit. gm did not balance it at the factory and that was the source of my problem!

WardVette

I called Spec today and he said all Spec clutches and flywheels are zero balanced from the factory... it is nearly impossible to get one out of balance. He told me to have the shop check to make sure the installation was done correctly. If everything looks okay, send it back to him and they will check and repair it. He said they don't do any labor warranty claims So even if they sent me a bad part which cost me an extra $700 in labor, they won't pay.