Greetings to all, I have been using the search engine digging through your great site trying to learn. I am struggling a bit so I thought I would go ahead and ask. I recently purchased a 2000 Ford Expedition 4wd, 5.4L. It has 50,000 miles on the odo. I noticed the oil was quite dark (as in black)and a bit on the sticky side when I purchased it. Seems to me people aren't as diligent with the maint. if they know they are about to trade in. Figured it just needed a service. I changed the oil/filter and put in Valvoline 5/30 dino oil. 2 K later the oil is black as coal. Whats up with that? I was planning on doing several short interval oil changes 2k to kinda flush things outta there then switch to a full synthetic. Granted, I have very little experience on this but I have never seen anything like this before. What should I do? I haven't even towed anything with it yet. Eventually it will be our family hauling mule for our ATV trailer and occasionally a 27 foot travel trailer. Any input you could offer a "greenhorn" would be appreciated. Great little site you have here. Looking foreward to an education.