I was about 150 miles into today's return trip home from the Oregon Coast when all of a sudden the motorhome started lurching a little bit. My first thought was fuel pump, but the 460 FI was running ...
I may have spoken too soon. I had similar symptoms on an older Ford C6 transmission that used a vacuum modulator valve. When the diaphragm failed it allowed transmission fluid to get suck into the engine, which resuted in loss of fluid and white smoke. Looking into the E4OD it appears it is all electronically controlled and does not have a vacuum line, so this does not appear to apply here. Sorry about the confusion.