While driving my car I noticed my temp gauge was above normal and climbing when I stopped and checked the overflow it was empty I filled it back up I did not see any leaks anywhere I drove my car through neighborhood short distance returned home checked the overflow again and once again it was very low. I pulled the dip stick and there is visably fluid from the radiator in the crankcase. I find no indications of any visable leaks my car starts properly and runs smoothly, anyone have any suggestions on where my next step in determining what is causing this problem, my car has never severely overheated, no smoke or moisture out the tailpipe?