Surprise under the truck today

[bdlight4]

It was a balmy 2 degrees this morning when I tried to start my truck. On the sixth try, it was either going to start or have dead battries. It started, but was not happy. Before it turned cold, i replaced the GPR & GP's, had the batteries tested and did an oil change with Rotella 10-30. Last year, the truck would start when it was -10 degrees without plugging it in. I did however park it in the garage. With the hard start, I decided to change the oil again to Rotella synthetic 5-40 this weekend. Anyway, while the truck was warming up in the driveway, I thought I would shovel some snow. That is when I noticed something on the ground under the truck. I looked a little closer, and it was engine oil. It looks like it leaked from up above the back side of the lower radiator hose. I'm guessing it was spitting it out while I was cranking the engine. It is currently not leaking any oil. Would anyone have an idea where this would be leaking from and why?

[alberta 7.3]

You're talking in the lower rad hose/below p/s pump area? Have a look at the oil cooler, the o-rings let go as they age.

[bdlight4]

When I opened the hood, I could see some oil on the back side of the lower radiator hose. Directly below was the oil on the ground. If it is the o rings, would they leak all the time? The truck has not had a leak before, and it is not leaking at this time. Not sure if it will leak if I was to start it again today.

[over200]

Yep..Oil cooler o-rings probably the front one but you might as well replace both sides..just did mine..$70 for the parts & 3 hours for the labor.

[highraven99]

ya definatly oil cooler, mine would quit leaking after the oil was warm. i literally just did mine, but mine only cost $40 for parts cause i went to the international dealer(ford had quoted me 70) youll spend more time getting it in and out because of its location than actually replacing the oring. its 4 orings and 2 gaskets that are needed

[bdlight4]

Thanks for the input. It's back under the truck I go.

[over200]

Also Note..... The hard part of the job is actually sliding the cooler pipe back into the elbows with the new o-rings on better to have a press then tapping with a hammer or mallet...the front elbow is made of a pop metal and will break easily..that will cost you about $100 if you break it.

[NCHornet]

The thinner weight oil will find any potential leak and find a way out. What 10w 30 oil did you find? Was it approved for diesels? The cold causes everything to contract, it could be it was just the coldness, but I would still replace the O rings.

[bdlight4]

I have always used Rotella T 10-30 in the winter and Rotella T 15-40 in the summer. Never had an oil leak before. After the truck started, the leak was gone. It does not leak while it sits or while it is running. It is like it just pushed the oil out while it was cranking. I'm going to switch the oil tonight and watch and see if it leaks while I crank the engine.