cdiesel

your Transit has a seperate Auto Trans oil cooling radiator - not a flow tru the coolent radiator. and it has a motor oil 'cooler' which is the oil filter head, with engine coolent circulating. More of a heat transfer device for quicker oil/coolent warm-up - for optimun motor emission temp regulation than pure 'cooler'

yea, after a drive and fully hot, remove the spark plugs, and let it sit for 1.5 hour, Come back with a helper to work the ignition key to crank it over while you watch for coolent pumping out of the plug holes. PROTECT YOUR EYES!. If coolent is pumping out of the holes - proceed to removal of cylinder head. Your facing a leaking head gasket, or cracked head. report back look at your oil dip stick and inside the oil filler cap. If mochachino creamy stuff is forming? same as above.