I agree the cylinder deactivation is just another thing to fail. The one hemi I tore apart had a needle bearing on the end of the lifter start to squeak. eventually it would have seized and chewed up the camshaft.
We have a few 07 5.3 Chevys with the afm crap. One of them has close to 700,000km on the stock engine. It’s never been opened up. Still has the stock timing chain and oil pump. It’s had the transmission replaced twice but the engine keeps on ticking, sometimes literally.
View my fuel log 2014 Mirage SE wussie cvt edition. 1.2 automatic: 37.7 mpg (US) ... 16.0 km/L ... 6.2 L/100 km ... 45.3 mpg (Imp)