C8 Convertible’s LT2 Fails Due to Broken Valve Spring… After Just 57 Miles

GM issued a service bulletin outlining this issue with the C8’s LT2 last fall, but it’s apparently still a problem.

We can only imagine the joy people feel when they take delivery of their shiny new C8 Corvette, especially if they’ve been waiting a while, as many have. We can also imagine the incredible disappointment felt by Micheal Crummer, a new C8 convertible owner whose LT2 V8 failed after he drove the car a mere 57 miles recently. Crummer posted pictures of the carnage on Facebook, which seem to indicate that a broken valve spring was the culprit.

Just last September, General Motors put out a service bulletin acknowledging the fact that strange noises, misfiring, and a check engine light were all symptoms of a possible broken valve spring, and that even if no cylinder leakage is observed, it’s necessary to replace all of the valve springs. This applies only to cars that were produced between June 1 and September 15, 2020.

We’ve seen this unfortunate issue pop up in the LT2 powerplants of some Corvette Forum members’ cars, and now, it has apparently struck Crummer’s new drop-top as well. Though he doesn’t say when his car was produced, the pictures he provides of his torn-down LT2 tell a pretty familiar story. They show a badly bent valve, caused by quite a bit of pressure that could have also damaged the head or the block itself.

Crummer does point out that he’s impressed the valve didn’t break, even though both the valve and keepers did. Another commenter points out that the spring manufacturer didn’t heat treat the springs properly, which is what causes them to break. Once GM became aware of the issue, it began verifying lot numbers and production dates before delivering the springs to the head assembly area.

This is obviously concerning and disappointing, but at least the damage is covered under warranty. Regardless, no one wants to have to get a new engine in their brand new vehicle, especially when it’s a somewhat expensive sports car. Regardless, these are often the breaks when you buy a brand new vehicle with a brand new engine design. Typically, early adopters play the role of a guinea pig when it comes to quality, and that certainly appears to be the case here.

Photos:Michael Crummer/Facebook

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