Well, helping a friend of mine make an oil choice for his truck. Currently, he's using a Fram filter (thought they were the best thing on the market) and whatever 5w-30 is on sale. Truck is a '98 with around 80K on it. Anyways, he'd like to extend drain intervals on out from the 3,000-4,000 intervals he is running now, so I suggested: Rotella-T 5w-40 Motorcraft filter BTW...want to hear something funny?? When I asked him about oil consumption, he stated, "That I don't even check my oil level, and as long as oil pressure is up and the engine isn't making any funny noises, then it will be alright...just the way I was brought up." Anyways, I feel my choices are just about as good as he is gonna get for wanting long drain-intervals on a 4.6L of this mileage that, with a doubt, has a good deal of varnish and deposits built up. Your thoughts?