GM should absolutely cover the cost of a new engine...but you'll need a lawyer.

Dear Car Talk | Jan 01, 1996
Dear Tom and Ray:
Len
RAY: We agree with you 100%, Len. Someone on the assembly line screwed up. And if you've got proof, you absolutely ought to pursue it.
TOM: General Motors probably pooh-poohs everyone who asks for a new engine. Think about it. If they took the time to fully investigate every claim of faulty engine manufacturing, that's all they'd be doing. They wouldn't have time to make cars any more.
RAY: So unfortunately, that leaves the onus on you to prove that they mismanufactured this engine. You need a lawyer, a deposition from your mechanic as to what he found in there, and pictures of the mismatched bearings (or the bearings themselves, if you've still got them).
TOM: And when you present all that stuff to them, they'll know, as Rooster Cogburn said in True Grit, "your intentions is serious." Then they'll know you're not like the thousands of other cry babies who don't even know why their engines conked out. Good luck, Len.
Len
RAY: We agree with you 100%, Len. Someone on the assembly line screwed up. And if you've got proof, you absolutely ought to pursue it.
TOM: General Motors probably pooh-poohs everyone who asks for a new engine. Think about it. If they took the time to fully investigate every claim of faulty engine manufacturing, that's all they'd be doing. They wouldn't have time to make cars any more.
RAY: So unfortunately, that leaves the onus on you to prove that they mismanufactured this engine. You need a lawyer, a deposition from your mechanic as to what he found in there, and pictures of the mismatched bearings (or the bearings themselves, if you've still got them).
TOM: And when you present all that stuff to them, they'll know, as Rooster Cogburn said in True Grit, "your intentions is serious." Then they'll know you're not like the thousands of other cry babies who don't even know why their engines conked out. Good luck, Len.
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