There are a couple of things that can cause oil to get into your coolant reservoir. A blown head gasket or a broken piston ring are the most common causes.
Do you have an oil cooler? I have heard that is a possible cause, as would be the head gaskets.
Low oil causing the coolant to heat up to the point in which it's doing more harm than good so it's pushed into the overflow
blown head gasket
This would be a primary symptom of a blown head-gasket.
A cracked head could be the cause of the problem. This, along with a cracked head gasket would allow engine coolant to enter the oil supply. Coolant and oil do not mix well and over time, the oil looses its capability to lubricate. Check your oil for white spots and check your coolant reservoir for oil residue.
It could be a couple of things first can you tell what color the oil is if it is brown/black it could mean your head gasket is blown or if it is red it is comming from the .trany
first you must determine what is actually contaminating the coolant,usually in the detroit series 60 engine it is fuel oil,usually caused by faulty injector cups!
Are you sure it's oil? Most likely is engine coolant from the radiator. Next would be transmission fluid. Or it could be from the reservoir holding the windshield washer fluid. Oil from the front is unlikely.
The oil filter on a crafter is to the left of the engine under the coolant reservoir.
you mean there is coolant in the oil or oil in the coolant either ways sounds like a head gasket problem.
if there is oil in the coolant system it could be a crack in the intake, a ruined intake gasket, a cracked cylinder head