I was reading some Ford commercial documents at work and noticed this blurb about extending the 3.5PFDI oil change interval from 10k to 15k miles. Do we think they actually did anything to accomplish this or just reprogrammed the computer? I'm hoping at least some research went into this and it wasn't a pure marketing decision. 15k miles seems like a lot on a work van that lives a hard life. Especially if it's motorcraft syn blend.