So I went to the dealership this morning to discuss my second separated tire in less than two months.....This is besides the point, we got to talking about the oil cooler and what temps we should see. At highway speed I normally see about a 12-14 degree split between coolant and oil, oil temp being the higher of the two. This is not pulling anything and doing anywhere from 70-85 mph. Typical temps: coolant-199-201 oil-210-214
I asked the service manager, who has been great the past two times ive been to this dealership, what Ford says is the normal temp split between oil and coolant and when is it time to bring it in for warranty. He said that anything over 4 degrees is a sign of concern and should be addressed. I told him I was above 10 degrees and he said "Yep you need a new oil cooler". This guy seems very knowledgeable and is cool about my delete on my truck. I knew I was heading down the road of needing my oil cooler replaced, but I was under the impression it was anywhere from 15-20 degrees difference in oil and coolant, not 4 degrees.
On a side note, we got to discussing headstuds and he said that the dealership always provides the option of ARP studs or OEM when doing a head gasket job. He said the truck is torn apart, might as well give the option of putting something better on. The customer has to pay the additional amount for the ARP though.