I went through this with my 03. At 600 miles, I noticed a stain at the bottom of the bell housing/rubber grommet. From the forum, I was made aware of the assembly lube situation. I waited until 3k, cleaning it up regurally. I went to the dealer for an oil change and reported it. The dealer looked at it and said it was assembly lube. I had my doubts. At 3500 miles I asked to have dye added to the oil and drove for about 400 more miles. It was not assembly lube, it was engine oil and after the dealer changed the rear main 4 times, twice under the direction of a hot shot Ford engineeer, I now drive a great 05 as a result of a Ford buyback. In fact, I own 4 and will pick up an 06 on Wed.) You may very well have assembly lube. Each of my 05's exhibited a wet looking bell housing for the first 3k or so. Never a drip however, so keep your eye on it and ask that dye be added to your oil for verification. Tod date, my 05's have been trouble and leak free.