EOT differential???
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Tuned
Joined: Mar 2007
Posts: 342
Likes: 1
From: South central kansas
EOT differential???
2005 F350 egr delete, etc coolant 2 years old, replaced oil cooler at time of egr delete also flushed system and replaced with ELC coolant. Installed IPR coolant filter and manifold at that time. Worked great for 2 years. Last night 70* air temp driving 70mph down highway unloaded coolant temp at 193* oil temp slowly rose to 220*. Pulling empty stock trailer home (2500lbs) oil rose to 238*. I run rotella T6 oil and am due for an oil change. Checked coolant filter a week ago and no debris whatsoever in it. Surely it can’t be time for another oil cooler. Any ideas?
Hotshot
Joined: Dec 2003
Posts: 15,368
Likes: 121
From: Stuttgart, Ar
Before you start tearing anything down, get a cold soak motor temperature on as many engine temperature sensors as you can IAT1 and IAT2, transmission, oil, and coolant to make sure you don't have a bad sensor. If they all match then do the test without pulling a trailer and see how close the temps are. Also make sure you check fan RPM to be sure the fan is working correctly. It should be "locked up" fully at that temperature difference. Also, does your heater seem to be working correctly? It could be a water pump failing and not the oil cooler.
Posting Guru
Joined: Apr 2015
Posts: 1,817
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From: Yakistan, WA
Before you start tearing anything down, get a cold soak motor temperature on as many engine temperature sensors as you can IAT1 and IAT2, transmission, oil, and coolant to make sure you don't have a bad sensor. If they all match then do the test without pulling a trailer and see how close the temps are. Also make sure you check fan RPM to be sure the fan is working correctly. It should be "locked up" fully at that temperature difference. Also, does your heater seem to be working correctly? It could be a water pump failing and not the oil cooler.
And when doing the ECT/EOT test be sure to be on as flat of a highway as possible.
Thread Starter
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Tuned
Joined: Mar 2007
Posts: 342
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From: South central kansas
i put it into tow/haul mode on way home with trailer and shift points changed, but i haven't heard the fan kick on high for a long time. I haven't seen ECT over 195 in a long time, not even in the summer with AC on! Will EOT cause fan to come on high even if coolant temps are normal? How common is an EOT sensor failure? Thank you.
Lead Driver
Joined: Jul 2004
Posts: 6,950
Likes: 510
From: Foothills, CA
i put it into tow/haul mode on way home with trailer and shift points changed, but i haven't heard the fan kick on high for a long time. I haven't seen ECT over 195 in a long time, not even in the summer with AC on! Will EOT cause fan to come on high even if coolant temps are normal? How common is an EOT sensor failure? Thank you.
There is an oil cooler bypass valve that has been subject of debate not so long ago, where the bypass valve itself could wear and allow oil to skip the cooler route...
On edit: Tim asked if you were monitoring FSS on your SG2 - is it showing fan ramp up?
Hotshot
Joined: Dec 2003
Posts: 15,368
Likes: 121
From: Stuttgart, Ar
i put it into tow/haul mode on way home with trailer and shift points changed, but i haven't heard the fan kick on high for a long time. I haven't seen ECT over 195 in a long time, not even in the summer with AC on! Will EOT cause fan to come on high even if coolant temps are normal? How common is an EOT sensor failure? Thank you.
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Tuned
Joined: Mar 2007
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From: South central kansas
Yes, egr valve is plugged in and in its factory location in the manifold. I have always been able to hear my fan when it ramps up (sounds like a jet)!
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Thread Starter
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Tuned
Joined: Mar 2007
Posts: 342
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From: South central kansas
I did the 50 mph delta test. Closest was 11* farthest was17*, averaged 14-15. I know this is right at the tolerance wher it is recommended to replace oil cooler, but I can’t believe it’s plugged in 20k miles since replaced and other work (elc coolant, coolant filter, new oil cooler, egr delete, vc9 flush). Where is the oil cooler bypass and how would I test or replace it?
Tuned
Joined: Apr 2011
Posts: 406
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From: Fox Island, WA
I did the 50 mph delta test. Closest was 11* farthest was17*, averaged 14-15. I know this is right at the tolerance wher it is recommended to replace oil cooler, but I can’t believe it’s plugged in 20k miles since replaced and other work (elc coolant, coolant filter, new oil cooler, egr delete, vc9 flush). Where is the oil cooler bypass and how would I test or replace it?
Lead Driver
Joined: Jul 2004
Posts: 6,950
Likes: 510
From: Foothills, CA
I did the 50 mph delta test. Closest was 11* farthest was17*, averaged 14-15. I know this is right at the tolerance wher it is recommended to replace oil cooler, but I can’t believe it’s plugged in 20k miles since replaced and other work (elc coolant, coolant filter, new oil cooler, egr delete, vc9 flush). Where is the oil cooler bypass and how would I test or replace it?
I'll see if I can find the thread and post it here...
Scott
I think this is the most comprehensive one, by copper.farm (who now owns a 6.4, be we try not to hold that against him
)https://www.ford-trucks.com/forums/1...fferences.html
Posting Guru
Joined: Mar 2014
Posts: 1,468
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From: Salt Lake City, utah
Was the oil cooler an OEM or an aftermarket from ebay? I have done the oil cooler bypass valve and saw no significant drop in temps but have the piece of mind knowing there is a new part in my oil filter housing and it was cheap. It’s also not unheard of for coolers to plug in that short amount of time depending on how well the initial coolant flush was done.
Hotshot
Joined: Jul 2005
Posts: 13,834
Likes: 25
From: Middle Tn.
I did the 50 mph delta test. Closest was 11* farthest was17*, averaged 14-15. I know this is right at the tolerance wher it is recommended to replace oil cooler, but I can’t believe it’s plugged in 20k miles since replaced and other work (elc coolant, coolant filter, new oil cooler, egr delete, vc9 flush). Where is the oil cooler bypass and how would I test or replace it?
Thread Starter
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Tuned
Joined: Mar 2007
Posts: 342
Likes: 1
From: South central kansas
Sorry, for the delay in response. Last weekend I changed the engine oil and added my maintenance dose of Hot Shot Secret. Finally got the truck out on the highway this weekend and noticed 10-11* difference at 50 mph and 15 or so difference at 75 mph with the AC on. Definitely not as alarming as it was before. I let my maintenance interval go a little long (almost 9k on the oil). I am just monitoring at this point and waiting. The biggest concern is when the thermostat opens the oil temp does not drop at all, and it seems to slowly increase the longer i drive. but i drove for over an hour and it reached 209 and stopped, but coolant hangs out at low 190's and down to 188 when thermostat opens. Just something to keep an eye on for now. At some point I will probably replace the oil cooler bypass valve, just for safety sake. And to answer an earlier question the oil cooler is factory ford, not aftermarket. I am at a loss as to how there is absolutely no residue in my coolant filter, but cooler is acting plugged.