i read on flatratetech.com that ford's TSB 02-1-9 recommends NOT using 5W20 oil in the Focus Zetec 2.0L engine. if true, this is totally contradictory to the owner's manual and what ford service dept puts in at a change. i can't find a way to access the text of TSBs on the net. does someone here know how to check this out and see what's the deal? i'd like to know before i ruin my engine. any help is appreciated... thanks