Ol' Blue has 250,000 on the ticker & still runs like new . I bought it with 70,000 on the clock & who knows what the story was prior to then , but I have run Valvoline 10/30 conventional ever since I have had her . I've been running that crappy ol' Fram "extra guard" for the last 8 to 10 years without a problem . To be fair , I must admit that the juice gets changed every 2,000 miles like clockwork , so I attribute that in itself to the longevity of the motor aside from the fact that is is a 4.0 liter . I had run the Power Flo filters for the first while , but those seemed to give me a dry start here & there especially if the truck sat for more than a day . Ever since switching to the "extra guard" , I have yet to experience a dry start unless she sat for a month .
So in the end , no matter how much bad you here about the Fram filter , my 4.0 still sounds & runs like new (knock on wood) . I was getting back about 5 1/2 quarts out of 6 on my oil changes which I thought was pretty good & started using a little 5 oz. bottle of Lucas fuel treatment with every fill up & in doing that I now get back 6 out of 6 quarts on my oil changes . There is obviously a benefit to that upper cylinder lubrication claim even though I really don't see a mileage increase per gallon that is noticeable . :brows: