My 2004 Saturn L 300 V6 series 2
 

My raditior has this think think milkshake looking stuff in it. It's is a very light color brown in it. Now I know it's not a blown head gasket cause it just passed smog with flying colors. It has never over heated before I notice and even now it still does not over heat. I notice have poured some sleat in the radiator just in case. I have just replaced the fuel pump and just two days ago replaced the radiator. Now water reserve still looks the same it looks like a milkshake still and I just notice now the radiator is leaking water. What next right!!! What is wrong with my car, can anyone help me please ???

What's the tranny look like?

When incompatible coolants are mixed, such as Dexcool and the green stuff, you get goop and sludge and funny colors. Additives can do this too. In any case, the solution to bad coolant is to flush the system. If you have done this already, such as when changing your radiator, then oil is entering the coolant system.

So it looked milkshake like, you passed inspection, then changed your radiator, and the color milkshake came back? It's hard to tell from the order in which you wrote things as to what order they occurred?

Remember with OBD2 vehicles having to not throw any codes to pass emissions, it's not the same as a tailpipe test. Also, if whatever is getting into your coolant is not getting into the cylinders, and as you state, it's probably not head gasket issue.

You did not respond when Gary asked about your transmission. The bottom of your radiator serves as a transmission fluid cooler, with lines to and from your transmission. The two sections, coolant and transmission fluid, are physically separated. However, if that physical barrier breaks down or leaks, you get transmission fluid and coolant mixing together.
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Not only do you get coolant with transmission fluid in the cooling system, you get transmission fluid with coolant in the transmission. The second can cause severe damage to your transmission if that is what is occurring here.

You stated the radiator is leaking water. I know you are using water as a generic term. My question is what color stuff is it leaking and where on the radiator is it leaking from? I don't know offhand what kind of pressure the transmission fluid is under in the cooler section of the radiator, but we know the coolant is under pressure, and I suppose it's possible that if the two are both pressurizing what is now a single chamber essentially, it may have ruptured a seal where the side tanks meet the core.

The other key thing to check is the oil dipstick. Do you see the milkshake in the crankcase when you check the dipstick for the oil, or does the oil look normal? Since we don't think it's a head gasket issue, I'm going to guess it looks normal. Please confirm.