oil in coolant resevoir

[BlackedOutXLT526]

Alrighty well upon going to check my fluids today I noticed I have a little oil in my over flow reservoir. Im not to sure what could be causing this, anybody have any ideas? I heard it could be from the intake manifold gasket going bad but I would like some input from fellow owners before I start ripping it apart! Thanks!:exp:

 

[SoHK_alumni]

Could be a lot of things, intake manifold gasket, head gasket or perhaps even the transmission cooler built into the radiator.

The earlier V8 Expo's had a water to oil cooler as well that could be the culprit but is not likely fitted to your 2000 even if it's a 5.0.

Look for signs of water in both the engine oil and transmission fluid, that will at least give your an idea where to start.

But, if it is engine oil, there's a fair chance the problem is with a head gasket and not a manifold gasket. I don't think (of course could be wrong) there's any high pressure oil to the manifold so a gasket failure there is probably more likely to get water into the oil than the other way around.

 

[BlackedOutXLT526]

Thanks, sorry to fail to mention it is a 4.0. I checked out the oil its not milky and there doesn't seem to be any water in the tranny fluid or oil.

 

[R&J Whitetails]

Thanks, sorry to fail to mention it is a 4.0. I checked out the oil its not milky and there doesn't seem to be any water in the tranny fluid or oil.

Sounds like a head gasket not sure on the fords but maybe a intake gasket. I don't work on many fords most gm products and when this happens it's usually the intake if there's oil in the coolant resivore and coolant in the oil is head gasket but like I said I'm not a ford guy.

 

[Runnin'OnEmpty]

Look inside the overflow tank while the engine is warmed
up and idleing, and check for bubbles. If you do see
bubbles, it's either from a cracked head or failed
headgasket. More likely the headgasket (in a 2000).

 

[BlackedOutXLT526]

Ok i got the truck all warmed up and checked the resevoir and there were a few bubbles present. Now i am not losing any oil and truck is running great like it always was. Does this rule out the tranny cooler inside the radiator? I am not losing any tranny fluid either.

 

[R&J Whitetails]

Ok i got the truck all warmed up and checked the resevoir and there were a few bubbles present. Now i am not losing any oil and truck is running great like it always was. Does this rule out the tranny cooler inside the radiator? I am not losing any tranny fluid either.

If it's bubbling inside the resivore it's sucking it in through the head gasket or possibly intake. You might not notice any performance change yet because its a very small leak and it's able to burn it off quick enough. You can go get one of those kits they sell to check for a leaking head gasket. It's some chemical in this tube type of thing and you put it over the radiator filler neck and if it changes color it's a head gasket. I have only used it one time but I can't rember what it's called It's in my other tool box at the other shop.

 

[BlackedOutXLT526]

ok thanks, I will pick up one of those kits and see what I come up with.