The black Permatex stuff works just fine, that's what I use. The most important thing is to be sure both the cover and the housing are as clean and as dry as possible, and to not get carried away with that stuff. A little goes a long way.

 

Now,thats advice straight from a Ford tech!

 

would you guys recommend buying a new cover from the dealership if mine is flaking kinda thick pieces of rust?

 

If it's on the outside, nah, I wouldn't worry about it. If it were me, I'd try cleaning it up a little with a wire brush and hit it with some rattlecan black or something just to pretty it up a little and try to stop any further rust.

 

If you are worried about it and have a 8.8 you could nab a finned cast aluminum cover off of an Explorer at a junkyard. No rust, runs cooler and is probably stronger if it would take a hit from something.

If you have a 9.75 unless the Expeditions did the same thing you are SOL and stuck with the stock steel one.

 

Factory replacements are about $20-$25 at your local Ford dealer.

 

Quintin must have taken this picture of mine about a month ago, same pattern with the Ultra Black. Cleaned both surfaces with a rag and mineral spirits and let the bead tack for about 30 minutes while I was finishing up other stuff. Torqued to specs and 3,000 miles later, still no leaks.