When the LS7 427ci V8 appeared for the C6 Corvette, we were all smiles. Finally, after decades, the 427 Corvette was a reality again, straight from General Motors with a warranty and all. It wasn’t the top-tier Corvette model (that claim was staked by the supercharged ZR-1) but it was a big-cube motor in a Corvette. Hell-freaking yes, hallelujah, and pass the torque. Except it seems, that some Corvette owners are not happy with issues that have sprung up with their LS7-powered cars, and have taken legal action against General Motors.
In a lawsuit, nineteen owners of C6 Corvettes made over 70 claims against GM, including “violations of the RICO Act, unjust enrichment, negligence and fraud”. The issue stems from the valve guides, which the owners claim suffer from excessive wear, leading to engine failures. The owners group accuses GM of ignoring or dropping basic tests because, as they claim, it would have led to the company having to investigate into the problem further and would have required repairs, something they think GM wasn’t willing to do.
The LS7 isn’t the only Corvette engine under the gun, either. The LT4 in the C7 Corvette has had a string of early failures, including a notable incident involving a press car being driven by a Fox News tester. GM has claimed that break-in procedures were not followed correctly or ignored, that some LT4 engines had contaminants in the oil, and that the Mobil 1 synthetic oil recommendation should be the only engine oil used.
(Courtesy: The Truth About Cars)
I was seriously in the market for a 2006 ZO6 until I discovered this problem. Most owners of these that are low mileage are in denial of any problem and won’t factor a “fix” into the asking price. So that dream is on hold…..
Weird, I am a mechanic and have worked on and even inspected the valve guides on a few instances. I’ve seen nothing and had no issues with the 40+ C6 427 corvettes that came through D&T Garage CA during my time here.