Well, that didn't work. Last year a very reasinable argument was made that the Vortec 5300 engine is designed in a way that creates excessive oil consumption. It's also designed in a way that doesn't warn you when an excessive amount of oil has been used.
However, a federal judge has ruled there isn't enough evidence to support the claims.
Even though GM has made multiple (failed) attempts to fix the issue. Or that GM completely redesigned the Generation V Vortec engine to remove all the fail points of Generation IV. Or that GM engines are blowing themselves apart from lack of lubrication.
Other than than that, there's nothing to support the claims. You can read more about the judge's decision here.
The plaintiff will be allowed to amend and re-file their lawsuit.