I would start by asking the shop how they 'flushed' the system. Unfortunately, this process is a multi-day affair to do it properly and a shop is either going to charge a lot for it or not do it right. It involves BACK-flushing from a cover/port near the oil cooler that requires a special kit to hook a hose onto, back flushing the heater core loop, using the proper chemicals in the correct order to remove iron (VC-9 or Restore Plus) and silicates (Restore), using distilled water in some steps, using pressurized air to pulse the system while flushing, getting the engine to full operating temperatures each time (takes at least 15 minutes), draining from the block and the lower radiator hose, and being patient enough to catch/inspect the residue and continue flushing until ALL of the casting sand and other crap is out of the system. Lots of flushes! It is not hard to perform, but it is very time consuming. There is a great writeup on this in the Tech Folder. Only a die-hard 6.0 specific mechanic would know these details. You would be shocked at what comes out of this backflushing process!

The reason Mark asked about the oil cooler brand is because there is only one specific make and model that has proven to be robust. That is the Ford Motorcraft 3C3Z-6A642-CA that is stamped "Made in USA." You will find when searching or contacting dealers that this part has been 'replaced' by a newer part number. Ford switched to a Chinese supplier to improve profit margin on these consumable parts. The newer part number has been reported to be less durable and the same as the Dorman part. This isn't to knock all China manufacturing because they can make as good or better parts if they were contracted to, but many companies go to China specifically to make parts at the lowest cost and minimally acceptable quality. The only way to purchase the 3C3Z-6A642-CA oil cooler is to call and see if a dealer still has an old one in stock (very rare) or from BulletProofDiesel the company who purchased ALL of the remaining stock from the US manufacturer when Ford dropped them. They have many in stock, and charge $438 each.

Finally, when replacing the coolant be sure to use a CAT EC-1 rated coolant and use distilled water.

Search around on this forum to learn more. You are not alone. Nearly everyone on here has had oil cooler problems. Owning a 6.0L requires learning about all these idiosyncrasies. It starts with the coolant and rolls into a giant s.h.i.t.ball of problems.

 

That is upsetting to have work done and right back to the same issue. I have several friends that fought the flush, reverse flush, new cooler, a year later same crap all over again. They finally had enough and sold the truck.

If you have the money and install experience, it may be time to ditch that OEM heat exchanger for an air to oil cooler. NEVER worry about that stuff again.

Just my opinion.

Good Luck

 

What are the coolant temps when the oil is 250*? That will tell you whether to look at the oil cooler or fan/rad.

 

it was a mishimoto cooler, I purchased it from ficm repair.

 

I would almost guarantee they didn't do a 6.0 enthusiast proper flush. Probably some water through it a time or 2 and called it good. I just am having a really hard time believing that even with a half a** flush job. That within 30 miles the cooler is clogged yet again. Truck has really low miles and I love it. I've really been debating a bpd air cooler to just be done with this garbage for good.

 

I have been thinking about that. I have 1000$ core charge coming back from my new injectors. Might just bite the bullet ans buy it.

 

coolant temps are right around 200*

 

my other suspicion is the rad fan. I've had a few sources claim coolant temps could be normal if rad fan wasnt working as should. I have NEVER heard the fan at highway speeds while temps are climbing.

 

That radiator isn't helping.

 

would you be willing to elaborate on what you mean? Thanks

 

Okay, So i have a backflush valve kit with the air and water inlet. I will try and get it done this week and see if there any improvements in temps. Right now its hard to say where temps are at because the only way they stop climbing is pulling over. I got to 253* before i got scared lol. I feel it would keep climbing indefinitely. I think I'm going to try grounding out the rad fan today and taking it for a drive. See if that does anything to improve temps.

 

I agree and would suspect it's something else, like a bad temp sensor. Nevertheless, you WILL likely have oil cooler problems if the system isn't properly flushed and you don't use the proper coolant. So I recommend doing this even if its just a sensor.

 

can you confirm if coolant and oil temp sensors are the same? I can swap them today atossed if that does the trick

 

The oil temperature sensor and the coolant temperature sensor are the same part.

 

One of the best reliability/longevity thing I ever did. Link that with the 7.3 fan clutch and you're golden, barring your cooling system is correct (coolant mixture/type and radiator health).

I monitor my truck like crazy, almost OCD status but I rarely look at oil temp anymore because it doesn't matter to me (within reason).

Good luck with your choice