Is frame/bodywork metal dipped?

[Chip276]

I was under the truck last night looking for the zerk fittings on the driveline. While there I noticed what look like rub spots on the underside paint, possibly back to the metal. One or two small patches, maybe 2"X1".
Other than paint is the metal treated or coated/dipped with anything?

 

[whippersnapper02]

Doubtful due to all the rust issues.

 

[Qwiksndmn]

How many zerks did you find? I have only found 2.

 

[Chip276]

I found 2, saw a thread on this forum or the other one but can't locate the all the ones listed there.