I have a 1991 Camaro RS with a 305.

I noticed the coolant in the engine disappearing with no apparent leaks anywhere in the system. After I refilled it I saw a presence of what looked like a fine mud in the coolant system. I'm assuming this brown stuff is a from an addition of oil to the system from some place. I'm guessing it may be a leak in they head gasket which would also explain the disappearance of the oil to begin with.

I haven't investigated anything yet, and just changed my oil about a month ago and didn't see any coolant in the oil that i changed. I was just wondering if there might be another cause to the disappearance of the coolant and the addition of all the crap into my cooling system.

 

Where did you check? If it was in the overflow bottle, I would not be alarmed, it could just be some fine rust settling out. Check to make sure it isn't your heater core.

 

no. it was straight in my radiator. I went to check the coolant level, took off the cap and realized that it was filled up half way. Then, when I filled it all this nasty looking muck was floating in it too. I also just realized that the heat doesn't work either, so it might be something in the heater core, but i'm not sure if that would explain all the mystery disappearance of the coolant in the first place.