I've searched and cannot find an answer for this. There are many threads about this problem on the S cars and it seems to be the oil cooler/heat exchanger, but I can't seem to find anything about a non S with this problem. I can't seem to find a oil cooler on my car, am I missing something?

I was driving about 70mph when the temp light came on orange, then quickly went red. I shifted to neutral and started to pull over. The light went off before I stopped so I put it back in gear and drove for about another 30 seconds. The light came back on red and the car died. I let it cool down and when I tried adding water, it ran straight out onto the ground. I pulled the intake and found the tube that runs from the water pump to the thermostat housing was cracked. I replaced it along with the thermostat housing. After putting it all back together, it ran fine, but when I rechecked the coolant level after the drive I found oil in the coolant reservoir. Any ideas on what could be causing this?