Hello all,

I have a 2006 F250 6.0 with 180k miles on it, arp headstuds, egr deleted, oil cooler, gaskets, work done at 95k have paperwork, running with a livewire tuner (used to monitor live gauges, have stuck with the tune the shop put on it with the engine work). To get to the point, I have invested to keep her in good shape, recently I have been noticing the eot and ect have been out of the +/- 7 - 14 degree range as I have seen on these forums. The ect seems to sit at 184 degrees sometimes bumping up to 186 - 188 while the eot is at 206 - 208 (this only happens at speeds over 50). At idle or 35ish mph, the temps stay within the above stated delta (184ect/196eot). This has been a recent observation that was not previously like, outside air temps ranging from the 60s to 90s. A few things I did prior to this was added the diesel archoil additive to a handful of tanks of fuel per the directions as well as the archoil additive to the last round of oil when I did the oil change. If anyone has any insight as to what might be going on, it would be most appreciated, I did look through the forums and was unable to find specifics. Could it be a thermostat, clogging oil cooler, bad sensor, pcm, etc???? Thanks for your time, looking forward to hearing back any information

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Bryan

 

There is also a puff of white smoke that comes out of the exhaust when I start the truck for the first time of the day.

 

Your ECT is a little low, I would change the thermostat first, get one from International, for some reason they seem to work better. After that recheck your temps.

 

Thank you for the info jet, i am by no means a mechanic in any way, i know these trucks can be fickle, i am currently averaging 19+ mpg, just changed oil and fuel filters. The truck still has been running the same as when i got it at 150k, trying to stay ahead of any major issues. To me this is concerning enough to reach out to folks here with the knowledge. I have been able to get solid info from these forums when ive previously had questions, going to look into a thermostat, anyone in the Charleston SC area have recomended mechanics?

 

Ive also recently had the coolant flushed.

 

when the coolant was flushed was it done with chemicals, or just water? Also what coolant was put back in?

 

I was on a trip with my family and ended up going to a dealership for the flush, not sure what they flushed with but i did make sure they used the ford gold coolant. I did this in hopes to help with the delta but it didnt make any difference. How it is now is how it was before the flush.

 

My ect was running low like that. Didnt think anything of it untill i did a trip into the mountains, ect went way up. Long story short, my thermostat was bad and staying partially open. Factory thermostat is set at 195, so now my truck runs warmer but Deltas stay where they should. And these 6.os like running hotter too...

 

Ford added a code in the newer year trucks just for that. It signals the check engine light to come on if there is a temp difference (delta) greater than 30 degrees between coolant temp and oil temp.I think it is P0128. Maybe the code is P012F. Looking it up...

 

I would recommend getting rid of the Ford gold coolant, there are many posts about it on here. I run Final Charge EC1 rated coolant as many have switched to the Cat EC1 rated coolants that help eliminate the oil cooler plugging problems./ If you search the forums for EC1 coolant or Ford gold coolant problems you will find a lot of info. In the mean time just make sure you maintain your Ford gold as recommended.

 

I appreciate the information all and will keep you posted. Crossing my fingers it's just replacing the thermostat.

 

Resurrecting this post because I am having similar issues. My truck is stock, however I recently added Archoil 9500 into the oil and the fuel treatment as well. After 200 miles my deltas started stayed under 10 even in the 90's with AC on, however my concern is after initially driving for 10 mins my ECT jumps to 202 while my EOT is still climbing up to 196, eventually my ECT will sit at 192-196 while my EOT remains 198-206. This never happened before Archoil additives, my truck was averaging 10-12 deltas. Should I be concerned or grateful? It's been 400+ miles now of this same "behavior".
Thermostat replaced at 176k, currently at 191k (about 1.5 years). Can't take it to my mechanic for another 2 weeks for personal reasons.
MPG is 13.5, sadly. It was 16-17 mpg last year running Diesel #2, but now every station has switched to B20. B20 is cheaper, my fuel filters seem to be running well with it, they never look that bad at all. I'm hoping the Archoil treamtment helps, but I didn't see any improvement after the first tank. Maybe I should drive the extra 10 mins to get Diesel #2?