Help! Flywheel question.

[Dsimps]

Hello, I have a 1995 Mustang gt 5.0 which I put in the shop 2 days ago to have the clutch and flywheel replaced. When I went to the shop today to pick up the car, it wasnt ready. I was told the supplier sent a Cobra flywheel instead of the GT flywheel which is causing the car to vibrate extremly. I couldnt stand to sit in it for more than a minute. They told me the Cobra flywheel had some kind of weight on it which caused the vibration. Tomarrow will make 3 days in the shop for a 1 day job. I am very uncomfortable about this whole situation. My question, is their explanation legit. Or could there be another problem. Im thinking that maybe the drive shaft wasnt put back on correctly. But Im no mechanic.

[MonteCitan]

I reallly really doubt the 93-95 cobras came with a .028 oz imbalance...

When I got my flywheel, it had in the box... a weight for the stock imbalance, .054 or thereabouts, and the .028 imbalance that I needed...

[Dsimps]

Day 4. The car is still in the shop..... Now its not the flywheel but the pressure plate has a defect... Im getting a little frustrated with these people... Sorry for the rant. LOL

[silverstangboy]

bad vibration is from them running the wrong counterweight, not to meantion that every flywheel, clutch, crankshaft, and balancer should be dynamically balanced together regardless of the base balance (54, 28, 0, whatever)