2014 Chevrolet 1500 - Bad design?

my mechanic told me that GM change the design on their truck engines around 2008 and it is causing the camshafts to fail requiring a new engine in trucks built between 2008-2014. Did they ever go back and redesign the engines or are they still using the bad design?

the 2014 GM V8 is known as the Generation V (or 5) LS V8. The 2005 to 2013 engines are known as the Gen IV (or 4) LS V8. So yes, there has been a re-design.