Possible oil temp issue... not a cooler issue

[b1er]

Hi all... I have a question for ya'll about oil temp in my truck... 2004 F250 KR CCSB...120,000 miles... after sitting over night my oil temp is always 4 degrees higher than coolant... I have an edge for monitoring... I noticed it happening last week and since it caught my eye, every morning I check before I start the truck... it's always 4 degrees high after sitting over night... can I safely assume that all EOT readings are now 3-4 degrees high?

Just for reference, I replaced the oil cooler this past weekend, flushed and refilled with CAT ELC, cleaned the turbo(vanes were stuck, big difference in power) and welded up the egr cooler... the oil cooler in there was date coded 2/14/2004 so it's the original and my temps with it were running 10 to 18 over ECT depending on what I was doing... now with the new cooler it runs 6 to 10 over ECT with the greatest delta being 12 degrees over after a run from 0 to 90 mph...

mods: edge, silverline exhaust.... coolant filter is in the shop but not installed( I know, I know, I ran out of time)... and while it was out I backflushed the egr cooler and it isn't remotely restricted... full garden hose flow was no problem and nothing came out of it when flushed, also no busted egr symptoms ever...

What do you folks think?

[amdriven2liv]

Sounds like the edge is off that far. When mine sits over night (like 10 plus hours) ECT-EOT-Trans are all with-in 1 degree.

How did your oil cooler look? Did you find crap in the inlet side of the coolant intake? Just curious, I'm exploring if a person could back flush one. Flushing through the coolant "outlet" on the oil cooler.

[tbisme]

I have a similar issue with the temps not reading the same, i just haven't swallowed the 75.00 sensor to see if it fixes it.
Was your cooler stopped up on the coolant side or the oil side?
My dealer says don't trust the monitor and replace the cooler, but you only saw a 6deg reduction in the oil temp no matter if the temp is off by 4 or not correct.

[b1er]

amdriven2liv, tbisme,
The cooler looked good... no crap in the coolant side, no crap in the oil... it was a bit restricted just seeing how the truck acts with the new cooler... the oil will drop it's temp quickly when the coolant drops...


I'm not down with spending the money either, to just guess at it... I have access to a nice temp gun and pyrometer... I may try to compare with the edge unit... is the oil filter housing a good place to get that temp for comparision?

I think the cooler made more of a difference than 6 degrees...if in fact the edge is reading off by 4 degrees, then that means the most I saw before the swap was 13 degrees and after is only 8 MAX...that puts normal driving in the 2 to 6 degree range...

the oil will cool off much much quicker now than before the swap... it'll even get back to around the 4 degree difference if it idles for a few minutes but it won't go below... and I understand how closely the temps are related and oil doesn't shed heat nearly as quickly as the coolant...

I guess until I get a known good temp reading to compare all I'll be doing is guessing...

[amdriven2liv]

Originally Posted by b1er

the oil will drop it's temp quickly when the coolant drops...the oil will cool off much much quicker now than before the swap...

This is what my concern for my cooler. Mine doesn't come down very fast. I really think my cooler is near time for replacing. I will reach 17-18 degrees difference when pulling steep grade. (Sexton grade on I-5 in Oregon) Pulling 8500-8800lbs.

[tbisme]

I checked mine this morning with no heat and the key on not running and I had a significant difference in the delta.
I checked both the temp senders with an IR type pyrometer and the brass on the senders were within 2 deg. dealer says it does not matter on the outside of the sender....Who knows, it is taking way to much brain power for this issue. I wish it wold fix itself for free. Maybe I will go get the sensor to rule it out.

[b1er]

that was mine also... it took forever to cool off even idling...

the most I've pulled with it is my jetski trailer... about 3k with the ski's and gear... thats what I was towning when it hit 17 on the interstate after a long hill... I was running the speed limit (70) and just cruising along...

[b1er]

Originally Posted by tbisme

I checked mine this morning with no heat and the key on not running and I had a significant difference in the delta.
I checked both the temp senders with an IR type pyrometer and the brass on the senders were within 2 deg. dealer says it does not matter on the outside of the sender....Who knows, it is taking way to much brain power for this issue. I wish it wold fix itself for free. Maybe I will go get the sensor to rule it out.

you'd think the sender body would be damn near what ever it's monitoring... if so, how far off was the edge reading? I'm wondering if the sensors can be skewed a bit over time... they just about have to be to some degree... these things aren't lab grade... they're the cheapest ford could find...

[tbisme]

For clarification, I am not using the edge.
I have a SCT TSX, and the the thing reads in celsius, but this morning the difference with the conversion was EOT-80.1 and ECT-112.3..... Now, I don't ever see it above 105C, which it about 221F on the worst hill but my coolant at the same time would be around200F. Puzzling part is my tech saying not to trust the monitor, or i would have already bought the sensor.

[b1er]

thats alot... that is after sitting all night right?