Hey, I've decided to finally join the sight and post after buying my 2006 f250 6.0 and doing a lot of research and work to my truck but have one final issue to resolve.
When I bought the truck last year it had 180k miles on it. The guy claimed all it needed was an oil cooler. I bought the truck and drove it home to find out the transmission fluid part of the radiator was busted, and the oil cooler was bad. I installed a new radiator, oil cooler, thermostat and heater valve and did a coolant flush. After that I tried to drive it and there was no power. so I diagnosed, there was a high pressure oil leak and my icp wasn't working. So when I broke it down to fix I replaced the dummy plugs, stand pipes, stc fitting, ipr, icp and pigtail and of course all gaskets that came up (Everything that I had read was common to fail I changed). When I got it all back together it ran perfect, nothing like the truck had ran before but I had a coolant leak at the hose from the oil cooler to egr cooler. I put on a new hose on and it fixed it. did a oil change motorcraft 15w-40. Now the truck drives and idles fine, icp and ipr values are good, FICM voltage is good .
In town driving around when the truck warms up the coolant stays around 190 and the oil gets between 190-208, after driving awhile at speeds less than 55 unloaded. I drove the truck on the highway and when I first get on the highway the coolant will go up to 218ish at the highest just for a few seconds before the fan kicks in and it will shoot all the way down to as low as 186. Driving on the highway at anything over 65 with the coolant at 188-190 the oil temperature will climb the farther I drive. a 30 minute drive on HWY has gotten my oil Temps up to 220 to 224 with the ECT still at 190, and then when I get off the HWY it will go down but stick around 210-215 all while coolant is normal temp.
The Egr cooler is capped off into the bottom of intake, looks like it came this way.
My question is, what could cause that high of oil temperature when coolant is at 190.
Should I try a backflush of oil cooler?
And if my coolant is too diluted, would that have anything to do with it? (not that would make sense but just a thought).
Im adding a coolant filter soon and I'm going back with the motorcraft gold coolant..
I'd hate to have to replace oil cooler again and love to drive the truck if anyone has any ideas I always have time to mess around with the truck, there are also no codes, I think I covered everything but if anymore information is needed just lmk.
Thanks!

 

Unfortunately all the debris you have in you cooling system and the fact you did a flush doesn't bode well for your future. On 6.0L you can't use a harsh cooling system flush otherwise you'll have particles that were loosened and break loose later clogging the oil cooler. If you need some kind of a chemical for flushing for oil (detergent) it must be mild and a coolant filter would help too. You may have to go through several oil coolers depending on what you used (VC-1) and this is assuming you did use a chemical flush.

 

Sound like the cooler is clogged again, and possible the thermostat has failed. Could also be the water pump impeller slipping on it's shaft. OEM is a plastic impeller. Do it once, and use the WP from Bulletproof Diesel.
You can't use a Dorman or off brand oil cooler. They just don't work. Get an OEM cooler for replacement. You need a Restore flush, then a couple rinses.
Restore Crack it open and replace the cooler, and probably thermostat. Refill with an ELC coolant. I like Shell Ultra. Shell Ultra
The 6.0 does better on a 10w30 oil. 40 weights shear to a 30 anyway, and it does not take long. A 30 goes in a 30 and comes out that way. Back then, oils were loaded with Zinc and Phos, todays dual rated oils, CK/SN are not. Motorcraft 10w30 works fine, and has boron that all those magic elixers like Rev-X and Hot Shots have.
Good luck, the 6.0 is like a trophy wife.... constant attention. It can be made to settle down, but it takes about 4,000 dollars in one shot to do it.

 

Thanks guys! Okay Dubbs I guess it's back to getting old girl open.
Logger- when I did the flush I just opened the block plugs and radiator hose on bottom of radiator and ran water through it I never did the heater core or oil cooler tho I didn't learn about doing them separate until after. I did the water hose then distilled only once then my elc coolant. Figured it was the cooler just was hop
ing for a miracle answer I guess. Thanks again guys!

 

Watch these.....
Then replace the oil cooler.