My first post on this Forum

2005 Super Duty ,4WD, Long Bed, Crew Cab. 146,000 miles
Truck does sit for weeks.

It has had all the 6.0 issues with the exception of the head bolts. All but one of the injectors replaced, Rebuilt turbo kit installed.

Engine is monitored with Edge set at stock

Continuous issue is water temp to oil temp difference exceeding 15 degrees.

After each of the following temp difference returned to 10-15 degrees for a period of time then started climbing again

6/2012 Cooling system flush and back wash, new coolant, 71,449 miles (material came out)

10/2012 EGR cleaned and checked, oil cooler replaced, new coolant 73,070

7/2014 Flush and back wash, new coolant 105,959 miles (material came out)

5/2016 EGR delete and cooler replaced, new coolant, 123,601 miles

7/2017 Cooling system backwashed, new coolant 140,000 miles (NO material came out)

10/2017 New overflow tank installed with new coolant 145,606 miles

Truck sat for most of Nov. Dec.

Now I am back to 200 degrees water to 240+ degrees oil when towing in 60 degree weather.

Towed in 18 degree weather and spread was still 40+ degrees. 189 water 229 oil

1/2018 Cooling system backwashed (NO material came out)

Continued 189 water, 235 oil temp

No restriction when back washed, no material comes out. What can possible clog the oil cooler again? Good oil pressure and water temperature. Even with good water temp could water pump not be flowing sufficiently?

Shell Rotella-T and S Rimula 15-40 oil

Caterpillar EC-1 coolant

Thanks Barry

 

Welcome to FTE Teamtiger. I don't believe that you have a problem at all. The max 15* delta test is to be performed under specific conditions. Please read this thread.


https://www.ford-trucks.com/forums/1...s-problem.html

 

 

I wouldn't like to see that differential, even when towing. I agree that if the coolant temp is still that low, then the engine can't be stressed for cooling.

Is the oil cooler that is currently in it an OEM cooler?

What are your cold soak oil and coolant temps (ie temps in the morning after sitting all night)?

 

Your water pump is fine or you'd show coolant running hot too. It is possible that you have a flow problem specifically on the cooler loop but from what I've learned whenever that happens it only ever happens in the cooler itself, not the other passages.

You can observe the flow through the cooler by setting up a backflush but instead just run the hose from the cooler outlet to the degas bottle and then run the engine.

 

Thanks all for the responses. Here is some additional info per your requests. When new truck ran 215 to 220 water temp when towing ( did not have oil temp reading) After first clean and back wash water temp dropped 20 degrees consistently and only reaches 220's under heavy towing in 90 plus temps. I tow two enclosed trailers. One is 16,000lbs the other 7,000lbs. 40 to 50 degree spread with heavy trailer, 35 to 40 degrees with lighter trailer. Unloaded I still have a 30 degree plus separation at 70 mph. Cold temps start out equal with water climbing quicker than oil, with oil surpassing water when it reaches 190. Both replacement oil coolers were OEM. We have done a chemical flush twice and the flush and back wash four times. So what could still be in the system to clog the filter? ( note nothing comes out during the last two back washes. First of recent two returned temps to normal in July mountain towing with light trailer. Second did nothing) What would a cooling filter catch at this point? Is there a problem using the Caterpillar EC-1 coolant? Thanks Barry

 

I understand knowing what is a nice to know, but it either is or it isn't so might as well cut straight to the chase and see what the flow is through the cooler. If it isn't then there is no question and we look for other causes, if it is the simple answer to the "what" is to pull it out, cut it open, and look.
There's basically nothing to be gained by postulating and theorizing right now.

 

How is the flow in the radiator, has it been replaced? Sediment could be blocking the passages in it.

 

Sounds like you just need to bite the bullet and do another new cooler. Also did you use a OEM ford oil cooler when you replaced the original???
If you did a doorman that may be the problem.......

 

to be honest looking at the reported numbers it sounds like your coolant side is cooling properly. but for some reason the oil side of the cooler isnt. whether it be a blockage in the oil cooler itself or the oil is getting trapped elsewhere in the engine. and throwing off the sensor readings.

Are you using aftermarket or factory oil filters?? since you stated your still running the factory style oil cooler im assuming you havent converted to a remote filter setup either. if the bypass valve has gotten stuck open or isnt getting depressed by an aftermarket filter it will allow the oil to bypass the oil cooler resulting in higher temps as well.

while you may not be seeing anything coming out with the back flushes even after switching to EC-1 the internal parts of the block still rust slowly over time.. coolants not perfect enough to 100% stop this from happening.. over time bits of the build up still break free and can clog the "artery's" of the engine..

 

Might be the valve in the housing for the oil by pass. I believe that there is a thread on it

 

Here is an update on the temperature differential. First we only replaced the oil cooler bypass valve. Wanted to do it first and had to wait on part.
Drove truck around 40 miles after replacement. All told I drove the truck for about an hour straight, so it was good and hot.
In town: Oil max 208/Coolant 190
Interstate at 70mph: Oil max 214/Coolant 190
Next we pulled apart the cooling system and installed a “Delta Kit”. Ran a line directly from the outlet of the oil cooler to return under the coolant reservoir. (Remember EGR delete) In essence, speeding up the water flow. We installed a coolant filter kit as well. While we had the coolant system apart, we acid flushed and installed new coolant as well this time. I drove 50 miles with city and highway. Nothing more than 10 degrees difference on Edge. Interstate at 70 mph was coolant 188/oil 198. Never went over 200 oil temp. Good results! Also an added bonus, my Edge oil temp is reading 4 degrees high. So actual on a scan tool test, coolant 188/oil 194.
With the truck loaded, but not towing around town corrected temps were equal. At 75 mph on three hour trip, corrected temps were coolant 190/oil 198.

Looks like we are good for now. Thanks to everyone for your thoughts. Barry

 

The poster doing the test on the bypass valve is dealing with other engine concerns right now. I too am interested to see if the bypass valve will correct the problem.

 

FYI, you linked back to this thread.