Bob N's 2001 Z06 just hit 200,000 miles on original engine, the only change many years ago was our Custom performance tune

Bob lives in high elevation but works at close to sealevel and drives his C5 Z06 daily to work from hot Ca summer heat to the cold and snow of winter
and still the engine has not had to have any internal engine fixes, nor other real problems other then normal maintenance

M6 Tranny did have to be rebuilt along with normal changes to shocks

Really shows how well designed Corvettes are