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Discussion Starter · #1 ·
I got home after a short drive today and noticed oil leaking under the truck. Popped the hood to discover the engine was covered with oil and it was coming out of the rad:banghead: I assumed it was the head gasket. I checked the dipstick and there is no hint of coolant in the oil. Seems like if oil is leaking into a pressurized cooling system that there should be coolant in the oil too :confused013:

It's a 96 12V swapped into a 99 F450. There isn't enough room to yank the head without pulling the motor so before I tackle that job I want to make sure I know what it is first! There isn't an oil cooler or tranny cooler plumbed into the rad so I know it's not that!

Thoughts?
 

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I got home after a short drive today and noticed oil leaking under the truck. Popped the hood to discover the engine was covered with oil and it was coming out of the rad:banghead: I assumed it was the head gasket. I checked the dipstick and there is no hint of coolant in the oil. Seems like if oil is leaking into a pressurized cooling system that there should be coolant in the oil too :confused013:

It's a 96 12V swapped into a 99 F450. There isn't enough room to yank the head without pulling the motor so before I tackle that job I want to make sure I know what it is first! There isn't an oil cooler or tranny cooler plumbed into the rad so I know it's not that!

Thoughts?
Your oil pressure will always over power your cooling system pressure while running. The only way that leak will go the other way is when the truck is shutdown and the coolant pressure is higher than the oil pressure. hopefully someone will chime in on other possible cause but the only thing coming to mind is a headgasket.
 

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Oil cooler
 

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It is part of the oil filter mount. It ties into the cooling system threw the engine itself.
 

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Oil cooler is behind the oil filter. It's about 12" tall and 6 inches wide. Re move it and test it with air pressure in a bucket of water. Been there done that! Mine had a hole between the oil valley and the water jacket.

Good luke!

Tom
 

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Mine was a 12 valve 97,. It had a hole between the oil passage and the water jacket way down deep inside the block. No one ever heard of it before.
The 24 valves had problems with external cracks on outside of the blocks.
They all have the same oil cooler behind the oil filter.

Let us know what you find.
 

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Discussion Starter · #9 ·
I just finished pulling the cooler out. pressured it up and it doesn't seem to be leaking and there was no obvious gasket issues but I'll replace them and put it back together as see what happens.
 

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Head gasket next??

If you pull engine to replace gasket, It would be good idea to have the block pressure tested as well as the head.
A good cylinder head shop should be able to do these tests.
 

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Discussion Starter · #11 ·
I reassembled it all and there are no obvious leaks anywhere. It will be tough to tell if it's leaking as there was so much oil in the cooling system I wasn't able to get it all out. It will likely take several system flushes to get it all out. I'll just have to keep an eye on fluid level I guess!
 

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Samething happened to me, execpt the oil mixed with antifreez it made a gray glue and was in/on everything including the oil-cooler,heater core all the hard to reach things. pressure wash everything.Mine problem was a head gasket a small track from water jacket to the oil port at clinder #5

98 4x4 kdp-killed 125studs #10 plate afc hard forward 5"ss/w duel6"tips pyro/boost 70sticks 5"lift 31575r16's
 

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Flush with a popular dish washer soap, I can't think of the name. Do a search.

Or try Dawn dish soap. glad it was just a head gasket.
How many miles on the engine??
 
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