I pulled this from D-tech maint. so everyone could comment.
Okay, that guy seems to be on the ball. More research got me some more good info, so here we go. The general ideas are this, laid out for future reference. Some things may be in the stickied FAQs around as well. Mod, if you like, please sticky. Anyone who knows their oil and has corrections/comments, please post/PM.
[SEARCH TERMS] Oil weight viscosity rating [/SEARCH TERMS]
OIL FAQ:
Synthetic oils have several advantages:
-They reduce wear. Only buy "SM" rated oils. SL/SJ cause more wear.
-They have superior low-temp viscosity.
-You can get 0-Wx oils in syn, but not dino.
-They have less (or no) viscocity improvement additives to wear out. This is one reason they can be run longer.
Oil ratings explained:
A 0-W40 oil will get no thinner than a 40 weight oil would at high temps, and no thicker than a 0 weight oil would at freezing. Unless you live in the desert, a 0W is better than a 5W. Never use a 10W on the Contour unless there are special circumstances (open-track racing in high-heat).
Myths Debunked:
-With modern oils you don't need to run two oils for varying temps.
-Synthetics will not harm gaskets, and won't cause leaks. If you switch on a damaged engine, the damage may be revealed sooner because the crud gets cleaned out. I'd rather know sooner than later that my gaskets are shot, but that's just me.
-Synthetic blends are not good. They do nothing for you.
-You don't need to follow the manual's ratings exactly.
What oil should I use in my Contour?
I would recommend one of several options, based on your driving situation:
If you run your car hard and want to be good to it:
-Run Mobil 1 0W-40 every 5k or even less.
If you mostly drive on the street and want it to last as long as possible, without excess cost/work.
-Run Mobil 1 0W-40 every 7.5k or so. Get an analysis to make sure it's okay the first time you go long.
You don't abuse it, plan on selling it well before engine wear becomes an issue, and/or want to save money:
-Run a quality 5W-30 dino oil every 3-5k.
One note: if you drive on dirt roads/dusty conditions a lot, or use cheap air filters or don't change your air filter, you might want to change the oil more often. An analysis will help you make that call.
What oil filter should I use?
-Not Fram. They have some good ones, and some real crap ones. Orange is bad.
-Motorcraft is cheap and very good. ($3-4)
-K&N is very pricey. ($12) If you race, it's worth it. The K&N (HP2010 fits the V-6) filters more oil and gets more stuff out.
-Fil
