this site speaks highly of Motorcraft blend. What specs make this oil such much better than others, like Pennzoil Conventional or Valvoline conventional?
I think its just that so many people use it and had no problems. That said they probably could have used Super tech and had no problems and got just as good as used oil analysis. The price at Walmart and the fact thats its made and endorsed by a major car company all come into play. Its as good as any and its a synthetic blend at conventional prices.
A semi-synthetic that's cheaper than most conventionals, puts up good used oil analysis, and shown to have good properties (cold flow, TBN retention, etc). What's not to like about it?
Nobody is saying that Pennzoil Conventional or Valvoline conventional aren't high quality oils, but MC costs less and is also a quality oil, it's just not advertised like the other two