what cause the oil go into the coolant system? on 2006 Mercedes-Benz E350 4MATIC

there are oil in the coolant reservoir. what can cause that? could it be the oil filter housing? cause there is a oil cooler attach.

by in Saint Paul, MN on February 02, 2011
3 answers
ANSWER by on February 02, 2011
WELL MANY POSS CAUSES BUT THE MAIN ONE THAT COMES TO MIND IS POSS HEAD GASKET BLOWN NOT POSITIVE ON THIS MODEL BUT COULD HAVE OIL COOLER SYST
ANSWER by on February 02, 2011
could be, also could be a damaged head gasket. pressure test system and observe and repair as needed
ANSWER by on October 17, 2011
It could caused by the bad radiator. There are two compartments in the radiator, one for cooling the for antifreeze and another for transmission fluid. The the wall breaches, trans fluid and antifreeze mixes. Just like you have oil in the antifreeze tank, I am sure trans oil also has antifreeze mixed in it. It could also causes bad trans shifting.