I just had a 30,000 service done at the local ford dealership, which included an automatic transmission flush and fluid change. When I got the reciept it listed mercon 5 for the new transmission fluid, even though the manual and dipstick say to only use mercon, not mercon 5 or mercon sp. The service manager said that Ford is now recommending mercon 5 because it is a better product, but he didn't have anything (like a TSB) to back this up with. I looked back at several older posts and someone had a link to a FORD website where it specifically says to only use only mercon for my year and transmission type.

I have the 4r100 4 speed automatic transmission in a 2003 v10 2wd. I probably drove about 60 miles with the mercon 5 fluid, and I'm making the dealer put the correct fluid back in tomorrow. Does anyone know if any damage could occur that quickly? Thank you.