If the flywheel failed it could have done a lot of damage especially if it was at high RPMs. At least the clutch including pressure plate, thorwout bearing and pilot bearing. The engine block should be inspected for damage from the flywheel falling apart and damaging the cases. The bellhousing ans transmission cases may have a hole in them and that is why the leak has occured. You should also check the input shaft and transmission internals for damage.
I say all of this because you want to get an idea of what caused the flywheel to break as that is not a common occurence.
I do think that getting a used transmission is going to be the best way to go but again you want to know if there was a failed part that caused it and why.
The mostlikely reason is that the car was driven very hard. It is possible that other things may have happened but that is something to consider when inspecting everything. You want to check everything while you have it apart as it cannot be inspected without, at least most of the areas I mentioned, the tranmission being out of the car.
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Monday, July 2nd, 2012 AT 2:01 PM