Mud residue on inside of radiator cap

[sjones]

This morning I was looking everything over on my SportTrac because I'm getting ready to take a road trip next week and I found a light mud residue on the inside of my radiator cap. None in the radiator fluid that I could see, just on the inside rim of the cap. I scheduled an apppointment to get a radiator flush tomorrow but has anyone run across this?

 

[Austin77]

You see it more in cars with dex-cool (chevy thing) but I haven't came across that in any of my fords. Basically its the coolant breaking down. Flush is a good idea!

 

[JohnnyO]

Flush it to be safe, I do mine every 3 years, but sometimes that will happen from a lot of short trips when the coolant doesn't get up to full temperature for very long and dissolve stuff. A similar thing can happen with the oil cap.

 

[koda2000]

have you. or perhaps a previous owner, ever put in a stop-leak product? anyway, flushing it is a good idea and while you at it check/replace your hoses. every time i've ever had a hose fail was right after a flush. no sense losing all that new antifreeze. if your hoses are swelled and/or soft change them. remember they rot from the inside, so just because they look okay doesn't mean they are.

 

[sjones]

have you. or perhaps a previous owner, ever put in a stop-leak product? anyway, flushing it is a good idea and while you at it check/replace your hoses. every time i've ever had a hose fail was right after a flush. no sense losing all that new antifreeze. if your hoses are swelled and/or soft change them. remember they rot from the inside, so just because they look okay doesn't mean they are.

Not sure about the stop leak but the previous owner did have the radiator replaced due to a radiator crack in 2009. Thanks for the advice on the hoses, i have a service visit scheduled today.