It hasn’t been much of a secret the LT4 6.2-liter supercharged V8 found in the C7 Corvette Z06 has had a few hiccups along the way, but the problem some owners are experiencing with the LS7 7.0-liter V8 in select C6 Corvettes may be lesser known.
A group of 19 owners, combining C7 Z06 and C6 Corvette drivers, have officially filed a proposed class-action lawsuit against General Motors, according to The Truth About Cars. C6 Corvette owners claim the LS7 V8 has issues with excessive valve guide wear, leading to engine failure. C7 Z06 owners continue to experience engine failure with some LT4 V8s dying with as little as 1,000 miles on the odometer.
The filing mentions GM has been aware of the valve guide wear problem, and has continually failed to address it. In total, the 19 owners have filed 70 claims.
According to owners, GM originally tested Corvettes with the “wiggle method,” but when it found the cars to have out of spec valve guides, the automaker dropped the test altogether because it “would lead to more repair and investigations than it wished to perform.”