1053857

Hello everyone,
I took my truck in because of an exhaust leak, and while picking it up, the mechanic tells me that I have a leak at the rear main seal.

Today I looked under the truck, and I do see some oil deposits/swelling but I don't see one area in particular where the leak is coming from. Unfortunately I am not as mechanically inclined as some of you may be, so it isn't something I can diagnose myself. Heck, maybe I'm not looking in the right area.

Here are 2 videos of me looking under the truck, as you can see there is some oil there, but like I said, I can't tell from where exactly.
Please note that it did rain/snow the other day so what you see can just be really dirty water from under the truck, and maybe no leak? I dont know.

Also notice that black cap moving, is that normal? When I press it in, a liquid does gush out kind of.
Oil pressure seems normal (about 5/8 of the gage, between half and three quarters)
When the mechanic mentionned it to me, he told one of his guys to check the oil level, he said it was fine.

I would like some more input on this, thanks!

Vehicle is 2005 F150 5.4L 4x4


http://puu.sh/lieFj/040d4943a2.jpg
http://puu.sh/lieG5/e024e43ded.jpg
http://puu.sh/lieFZ/ebe334e084.jpg

1053857

Anyone?

1053857

Up!

Any ideas? I have added oil once since, so there is a slow leak somewhere, but still don't know.

Thanks!