I bought a 96 rs. When I got it the antifreeze was little low but nothing major. The oil that was in the the car was a dark oil. Now I changed the oil about three times, each time the oil would turn a creamy colour. The last time I changed it I ran the car for a bit the was no change in colour, then let it sit for a day then it turned creamy. The car doesn't run hot. There is a little bit of condensation coming out of exhaust. But no other signs. I was told head or intake gasket.

 

My guess would be intake if antifreeze is get into the oil.. DO NOT DRIVE IT!!!!. When antifreeze is subjected to the high pressure that exists in the oil pump it breaks down, one of the chemicals release is a acid. That acid will melt the Babbitt on the bearings very quickly and this will trash the motor. THIS IS THE NUMBER ONE KILLER FOR 3800's. Bad intakes gaskets are so common there was a lawsuit back in 08.

If I bought a 96 today with no issues I would be tempted to do the intake gasket just to be safe.

I am not saying it cannot be the head gaskets but when the head gasket goes it normally blows between the coolant and the cylinder. (these cars have no pressurized oil passages in the heads like on a car with a over head cam.) For coolant to get to the oil the leak would be so bad that the coolant would have to pool in the cylinder and leak around the rings. If that was happening you should get a big poof of steam and the PCM should set a random misfire because the coolant would short out the spark plug until the coolant burn off. Don't get me worn you could have a bad head gasket and a bad intake but most likely the coolant in the oil is coming from the intake.

After saying all that, if you do the head gaskets then you have to do the intake. Head gaskets do fail on these cars but that is mostly due to not changing the coolant all intakes fail it is just a matter of when. If you are not sure how the car has been maintained since the car was new I would just do the head gaskets. Removing the intake is about 60% of the work needed to do the head gaskets.

 

when you get an intake gasket for it. make sure you get one for the RWD 3800. the gaskets for the side of the intake that go against the cylinder heads are the same but the end pieces don't work between the FWD and RWD 3800. I made that mistake after ordering gaskets for my 3800 before seeing what the gaskets it had looked like.