Wet areas on rear axle and other places (leaks?) (1 Viewer)

[bk928323]

I haven't had much chance to drive this truck, but today I drove it around to take some pictures of the undercarriage, and I came across some wet spots.

I was wondering what the issues are, if I should address it right away and how much these will cost to fix.

Thanks

 

[FxFormat]

2nd pic of the skid plate, could be any fluid, you need to remove the skidplate to inspect where it's coming from.

top pic is rear diff fill plug weeping, the area to the frame im not sure, AC line condensing perhaps?