I've been watching the temp rise while towing up hills and constantly seeing deltas over 20degrees while regular driving. The truck was studded and all upgrades done 2 years ago with a new oil coole,r coolant filter, blue spring, dummy plugs, 6.4 banjo bolts, garret turbo, GoGo intake with egr delete, cfm intake elbow and bulletproof water-pump. I'm sure I'm missing something. we flushed the motor and heating system before we put motor back together. When I checked the coolant filter the first time I changed it it was clean. My mechanic is leaning towards a plugged oil cooler. What do you guys think. I,ve seen oil temps close to 240. Thanks

 

A correct test is performed unloaded, on flat ground @65 mph for 15 minutes.

 

Yep done several times seeing over 20 degree difference

 

Then it sounds like your oil cooler is plugging up.

 

Oil cooler plugged.
Did you use ford oem when replaced 2 years ago?

 

What is your ECT, EOT and TFT read after an overnight cold soak? And is your EGR valve still plugged in even though you have an EGR cooler delete? It needs to be plugged in for proper cooling fan ( clutch fan ) operation.

 

Ford oem oil cooler installed. EGR valve is plugged in.I just dont get it the old oil cooler was clean put we replaced it anyway. It had 90,000 miles on it not the new one has 30,000 miles and plugs up? with a filter installed

 

I was wondering about that valve under the oil filter if that was not working properly if it would cause this?

 

good point, you could be bypassing the cooler some...

How do you know the old one was good, did you cut it open? or was it just by temps....

 

Not sure if you guys remember, but I did not have a bypass valve in for a while on a brand new oil cooler, so oil was bypassing all the time. My max delta was 13.

Ithaca, how long since all the work was done, and what coolant are you using?

 

At what speed did you see eot at 240?

 

I feel your pain. Been fighting the same issue for a while. Replaced the new cooler and problem remained. Then replaced the bypass valve in the filter base, no help. Most recently tried a new degas cap (old one did fail the pressure test) but still no change. I'll be following this thread.

 

replaced cooler less than 2 years ago. Looking into the ports of the old cooler and can not see any buildup of any sort also never had this proplem before even before head gaskets were replaced. My mechanic says to keep an eye on it but does not believe there is a problem. Coolant filter is flowing well with nothing in it some dark discoloration but no particles. He does not believe the cooler is plugged. I guess I'll keep an eye on it and make sure the fan is turning on as it should. It has not overheated that I know of degas bottle clean around cap.

 

Is there any sediment in the bottom of the degas bottle?

Did you recently change the oil? Could be possibly filter didn't seat fully or a spring/valve inside the filter housing got hung up.

 

degas bottle clean and just had the oil changed