Some background info,

2006 6.0 with 158,000 miles

Heads ARP'd and heads checked and surfaced by machine shop.
New EGR and oil coolers.
New water pump, fan clutch, fan belt tensioner, thermostat.
No modifications at all on the truck

I added a Scan Gauge II when I studded the heads and changed the coolers. Water temp stays where it should and fan kicks in around 215-218 water temp as it should when towing. Not towing the water temp usually stays under 200 degrees depending on the ambient temperature. The water temp runs where I'd expect it to whether or not I'm towing. But my EOT temps are high. Not towing i'm around 10-15 degrees higher on my EOT. Towing the delta gets around 30 degrees higher. Other than the high EOT's, the truck runs great and is well taken care of.

Admittedly I cheaped out on the oil cooler (I know, stupid). I've learned the hard way on other things with these 6.0's to steer clear of the cheap parts. I'm thinking that my oil cooler is crap and not working worth a damn. So I'm looking to getting a genuine Ford oil cooler. But before I drop the coin on a good oil cooler, are there any other ideas on what could be causing my high EOT's besides the oil cooler? Just for the record, I'm not going to delete the EGR cooler due to emission testing in my state. Thanks in advance for any help.

 

Sounds like the oil cooler is plugged.

You can try backflushing it. A Google search should bring up some options on doing that (one by fixur6 that I can recall).

Have you upgraded to an EC-2 rated ELC coolant?

The original Ford Gold coolant is a problem. It "can" work as long as you flush it every 40k miles or so AND as long as it isn't exposed to excess heat and combustion gasses. Bottom line, it is VERY common to have it "gel up", and you are better off with the EC-1 rated coolant.

 

The oil cooler bypass valve is another possibility, but not common. It could be letting oil bypass the cooler and run straight you the filter. If you're doing an oil cooler, go ahead and do the bypass valve too.

Clogged kity could cause highest temps too

 

Problem solved. Stay away from cheap azz Chinese parts. I pulled the cheap cooler out and put a genuine Ford oil cooler in. The oil temps are normal now. Thanks for the responses gents.

 

Nice return to answer the problem!
Thank you