Do EcoBoost engines accumulate contaminants in the engine oil faster/differantly than naturally aspirated engines? As of today, 11/17/19, our ’19 Explorer with the 3.5L EcoBoost has 9,100 miles on it. I’ve changed oil using 5W30 Mobil1 Synthetic and Motorcraft FL500S oil filters at the following mileage intervals: - 1,040 - 4,100 - 6,500 Even a few hundred miles after the oil change, I'm suprised how "dark" the engine oil is. This is the first TT vehicle we’ve ever owned. It runs fine, I have no reason to believe there are any issues. Maybe it’s me... Maybe I should send a sample to Blackstone Labs for analysis?