I'm running Mobile 1 "High Mileage" synthetic oil. 10W40 in the brutal summertime (Texas constant triple-digit heat), 10W30 during the springtime and autumn mild temperatures, and 5W30 during our brief, but cold north Texas winter months. My 30v 2.8V6 seems pretty happy with these weights.

 

And the part number for the big Mobil 1 filter is M1-301. I use that along with their 0w-40 "Euro formula" oil and have had pretty good results. Crazy is right though, it did make the lifters a little bit noisy. Doesn't bother me, but I may try switching to 5w-30 or 10w-40 or something and see if that helps.

 

Ya the 5w-40 pennzoil ultra euro made it shut up a little. I personall use the mann w940/25 but any very large filter should work

 

And just one more thing, oil is cheap, relatively speaking. So if you don't like what you put in it the first time, it ain't no huge deal to change it short of the recommended oil change interval. Eventually you'll find something you like and that works well with your car. Everyone here has given some good oils to try so just got for it

 

^That's a good point too. Your motor isn't going to asplode if you put a little bit heavier or lighter weight/viscosity oil in it. If you put in 0w-40 and notice that you're not getting good oil pressure at idle or your lifters start chatting a little more than you'd like, just try something else.