squidlips

Weird question. Does antifreeze get need to be changed like oil? I popped my rad cap and whats inside is this brown milky liquid. Now my truck doesn't overheat, doesn't burn oil, doesn't burn antifreeze. Is it possible its just dirty? What else could cause this? Also the antifreeze in the over flow take is green like it just came out of the jug, why aren't they the same color? Here's whats in there.

95_5.8

Typically if it's a brown milky color, you have oil mixed in with your coolant. But to answer the question, your coolant system does break down over time causing it to not work correctly. I know gm 3800 motors are notorious for the coolant turning to sludge which is a strong sign for either a blown intake or head gasket. Mixing dextrol with Otc green coolant isn't a good thing either.

RLXXI

The coolant in that tester looks old, coolant does require changing over a period of time, the two ways I was taught was to check the specific gravity as you are with that tester the other was to check it's electrolysis with a dvom.


Place the positive lead on the battery + and dip the ground lead into the coolant without touching the radiator or over flow degas bottle, if it reads close to or more than 1v it needs to be changed.

joshtowal

Ford recommends coolant replacement every 30,000 miles for your truck on the normal service table. The additives in the coolant are used up over time. Namely, the anti-corrosive. The brown color is probably corrosion in the cooling system. Nobody ever bothers to change the coolant regularly and then wants to cuss the vehicle when one piece after another in the system starts going out. Not saying that you are, just my 2 cents from experience. lol

techrep

iTrader: (1)

I do... I change my brake fluid too.. often forgoten also...

jayber

orange and green antifreeze mixed will make brown color.

Chris_1

iTrader: (1)

The anti freezing properties don't break down but as mentioned above, the corrosion inhibitors do. And your motor.s made of iron, so the coolant starts to get a little rusty looking.
You will want to flush that system completely and refill it with fresh anti freeze mixed 50 - 50 with water.
Straight antifreeze does not work as well as a 50-50 mix.
Clean the rad cap up real good too if it's got crap on it.

choate

Mine was the same way. Doesn't burn oil or coolant and the oil looks good. No sign of coolant in that. Recently had the coolant flushed and afterwards noticed some sludge in the overflow tank since they didn't wash that out or put any in that. Looked like oil to me and it was slick but didn't smell like oil. I was pretty worried about it for a while but the truck is solid so I was confused too.

Does your truck have a tranny cooler on it? Mine does and a mechanic said my lines could be leaking into coolant inside the radiator and over time making it that browish slick stuff. I did have my system flushed and cleaned out the tank the best I could w it still on the truck.

89_loud_pipes

If your vehicle runs hot it can break down some of the sludge and dirt in the cooling system if there is any, this will make the coolant look dirty and brown. Easy way to tell is to pop off the main hose going from the radiator to the thermostat housing with a drain pan under it. If you have a little miss tint like a brown or if it has little sludge particles in it you may want to flush your system and put in all new 50/50 mix.