ptclk63

I have a 2007 clk63 55k miles if i really get on it, it will push up the oil stick and blow oil out the tube. I have taken care of the problem by drilling a hole in the oil filler tube and placing a piece of wire thru. Im just curious if anyone has experienced the same. I have dumped the oil and put back the correct 9 quart amount. Is there a pvc valve that could be bad???