[SOLVED] Rusty Coolant Or Headgasket?

[FullBlownModz]

I took out the rad a month ago and flushed water through it with my garden hose. The coolant (water) was really brown and rusty. I removed it because I had another radiator ready to go in, but once I learned that it was the wrong size, I threw the old one back in.
Fast forward to today where the truck is overheating. The needle would get to the L on normal and I would drive it back home and park it. The coolant would boil through the Overflow container. My brothers truck did the same thing, and was fixed by just a radiator. So, i got a new radiator and the old coolant looks like it does HERE. I cant tell if it just got more rusty or if there is some oil mixed in too. The radiator has been needing replacement. The drain plug doesn't even drain it because it is so clogged with rust.
Does this look like oil in there?
Im going to flush the system a few times before putting in the new radiator, so i dont clog the new one up with rust. I should probably go buy some distilled water too

 

[FullBlownModz]

This issue has been resolved. The culprit: MUD IN THE DANG RADIATOR! I went ahead and replaced the radiator, and I found THIS in the old one. I had probably flushed the system 4 or 5 times, and the system wasnt getting much cleaner before the replacement. Now the water comes out nice and clear.
Plus, im not overheating while idling anymore!