Has anyone wondered why Motorcraft's 5w-20 is a synthetic blend? I looked in my owner's manual and it specifies 5W-20 but the fact remains its a synth blend. So the used oil analysis should make it known that the 5W-20, however well/bad it performs is a synth blend, not a dino. I'd like to see a Group I or II 5W-20 dino oil used analysis test. Ford switched to a synth blend becuase a dino 5W-20 thinned out too quickly plus it breaks down too easily (lower thermal stability) hence the synthetic blend. Sorry but there's no way I'm using 5W-20 in the future. If the modular motors could handle dino 5W-30 for the past 12 years, then why change to synth blend 5W-20?