I have read numerous pros and cons for Motorcraft 5w-20 (Conoco) oil. I have seen alot of UOA's for Mazdas using this oil and they look very impressive but how about a hard worked modular Ford engine ? I seen a real recent one on a V10 used during summer conditions and trailer towing which is an excellent example of a hard worked engine. One example of this is insufficient data for a trend. So how about some data to back up the "THIS IS PHENOMINAL OIL" or "THIS IS WATER DISGUISED AS OIL" arguments.