Head Gasket
 

How can you tell if yours is blown? Right now my radiator fluid keeps losing it's color and changes from orange to a grey like color. :\ Afraid it's oil. Help someone? :D

Normally you will have antifreeze in the oil, the upper radiator hose will be bulging out from the pressure, and if you do a compression check you would find 2 cylinder side by side with low pressure.

What would cause the coolant in the radiator to change from it's normal color to grey/black? It's still got some color in it, but looks as though oil was mixed into it or something. Could that just be a dirty radiator, or something?

Gah. :P Stupid truck. Haha

I'm not sure what would cause it to be grey or black off hand. Usually when oil gets in or there is rust in the coolant it turns brown.

I heard it's because of the gasket leaking or something.

head gasket
 

best luck I have had finding blown head gasket is by using the compression check like someone else mentioned. If it is really bad they oil can get water in it and turn about the color of hot chocolate. Just ent thru blown heads on my 2000 3.0L and had to replace both due to cracks. Not a real fun job but it is done. I did find a blown gaket on one side and looked like it had been for a while. I also found lot of other broblems once I was in there with valves and lifters still tracking the lifte problem. Wish you luck!

compression check will be most helpful and narrow down the possibilities. may not be just the gasket. you may have cracked the head. but why would the head crack?
mine blew out a while back right after i bought it used. stoopid. coolant would boil outta the reservoir and smelled like exhaust. truck stumbled through acceleration. tore down to the block. drivers side head cracked at the first cylinder (closest to front of engine). three of the exhaust manifold bolts had sheared off. removed all accesories, and then water pump to investigate an apparent leak to discover the rotor in the water pump was non existant. so i found the culprits.
point is get to the source of the problem or you may be doing it twice.