i`m overall quite happy with my 6.2 and reasonably happy towing a 4500 pound, 7x14 cargo trailer with it (several 1500km days). I don't think a could say the same for the 5.3, having previously towed other trailers with the 5.3 in a Sierra. That said, I do miss my 2500 Sierra with the 6.6 diesel on the big towing days.