Bought a truck on the local classifieds for $1600 - 06 Ram 1500 with hemi for a parts truck. Truck runs/drives great, bit of an exhaust leak on the passenger side throwing an 02 sensor code, otherwise seems great.

Problem I found today is that there is a 1/2" layer of oil on top of the coolant in the overflow tank. There's no coolant in the oil, it's spotless. Any ideas where this oil is coming from?
The coolant system isn't building unusual pressure (the cap doesn't blow off when flogging it around the farm) so I doubt it's the head gasket.

Any ideas out there?

 

You can do a block test to make sure.

 

Are you sure its oil and not transmission fluid? If you had a gasket failure between the oil passage to the coolant passage you might end up with mostly oil in the coolant, but I would expect at least some cross contamination.

 

Simple. Blown head gaskets or cracked heads. Either way, the heads gotta come off and get checked.

 

[QUOTE=freestyledude;3184417]Bought a truck on the local classifieds for $1600 - 06 Ram 1500 with hemi for a parts truck. Truck runs/drives great, bit of an exhaust leak on the passenger side throwing an 02 sensor code, otherwise seems great.

Problem I found today is that there is a 1/2" layer of oil on top of the coolant in the overflow tank. There's no coolant in the oil, it's spotless. Any ideas where this oil is coming from?
The coolant system isn't building unusual pressure (the cap doesn't blow off when flogging it around the farm) so I doubt it's the head gasket.

Any ideas out there?[/QUOTE

 

 

[QUOTE=Jerryks;3500915]Is there an oil cooler that involves coolant on the engine?