2010 F150 4.6L 2V, currently 58k miles. The previous oil change was Mobil 1 5w20 (not EP) and I ran for 10k. My driving is 85% or more steady cruise/interstate driving (55-75 MPH). During the previous OCI, I kept a close eye on oil level and visual condition, and no oil was needed for top off during the entire run. The current oil is Pennzoil Platinum 5w20, and 8k into this change, I have had to add a half quart of oil for top off. There has been no difference in my driving habits, or the routes driven. The change/fill procedure and location was the same as before and have always done on each of our 4 vehicles. I am sure there is a "chemical" reason for this, and am looking forward to some of the possible reasons that will be brought forth. No bias on my part to either product, just an innate curiosity. Thanks in advance.