There have been complaints about the 5.3L engine since 2007, yet GM has done nothing about it. With only 62000 miles, I had to have $1100 worth of repairs to the engine, due to poor design. The engine had developed a solid engine 'miss', only 20,000 miles after purchasing the truck used. The independent mechanic shop had to look up the cause/effect/recommended repair on their independent web reference. The result: due to a design fault in the valve cover(s) , a replacement had been designed by GM that - supposedly - fixed the problem; oh, that and a premature tune-up, because the spark plugs had been completely gunked up with oil from the poor design. Now, only 20,000 miles later, the same problem has popped up again. A different repair shop described the same remedy as before! This shop owner said he LOVED this engine, as it earned him a lot of money! Personally, he owns a similar truck, but with the 6.0 L engine.