So this morning I decided to inspect my under-the-hood areas and I noticed my overflow was a bit empty (picture attached) and upon further inspection I saw black flakes at the bottom which doesnt seem right!
Some people online say it's a head gasket but I doubt since this truck does not puff blue exhaust or have any oil-coolant mixtures so I'm assuming it's the inside of a cooling hose breaking down after all these years and hot summers.

Only got a couple questions for the folks on here with more knowledge than I do:
1. Since these reservoirs were not given any paint (Arctic or not per the FSM) nor do I have any head gasket issues, what hoses should I inspect for anything out of the ordinary? Dont have any suitable drain pans at the moment to do anything on the spot right now though.
2. Is the lack of coolant with black flakes a signal of any other issues or just some hose or hoses signalling they're on their way out?
3. I'm going to clean out the flakes and add some pink coolant (For Toyota 1990+) although the one in my truck right now is green (bottle for the green does not mention anything for Toyota), is this a good idea or should I stick with green?

Oh and try to empty it beforehand, made a bit of a mess doing it with a half full washer tank, luckily I had a sparkling water bottle on hand cause of the heat to fix that!!!

Any input is really appreciated, thank you in advance! Cheers!

 

Should be fine as long as its not overheating. Just pop open the little drain plug and have it drain into water jugs bottles or whatever. I had a 4 gal water jug with a funnel to catch the coolant. Reused that shit.

the black flakes could just be the hose like you said or maybe a flake of something from inside the rad or engine.

 

The toyota coolant is best because the mixture of metals. Green can cause pitting. You can't go wrong with the oem coolant.

 

Might be the radiator at worst, maybe a hose. I'll see if I can look at the hoses when i do a full system flush whenever that may be, but since I got a full set of jackstands and a new stool on wheels that might be soon! No guarantees though, its HOT as TITS lately!!!! Need to find some bottles to put aside for all this coolant though, think the FSM said it was 4.9 Litres/Gallons cant recall where I saw that though. Thanks for the reply!

Last thing I want is a messed up cooling system!!! Do you know what the OEM/closest to OEM coolant is? Should get this green stuff out ASAP since I do not want any pitting/damage of sorts, I'll use the pink stuff I got in a pinch or OEM if its the best by far. Thanks in advance!

 

Its maybe over a gallon of coolant. Grab a couple jugs from the dealer, theyre inexpensive. And grab some distilled water for a couple bucks at walmart.