possible coolant in oil in 2004 3.5 colorado engine

[wnyfarmboy]

I think I may be having an issue with my 3.5 engine. The engine has 95K, has had the oil changed every 3000 miles and has never been overheated. I noticed that there was some orange type bubble scum on top of the oil in the drain pan the last time I changed oil. After a little while it disappeared. I changed the oil again over the weekend after 2400 miles and this time it was the same thing again only more than last time. It would appear the the coolant level in the reservoir has gone down just slightly. There is no build up or residue on the oil filler cap. The truck runs good and shows nothing unusual from the exhaust. The oil when drained cold looks fine with no milkiness, just the orange bubble type scum on top that disappears after a short while. Any ideas what the cause or cure for this would be? Any information would be greatly appreciated.

[txab]

Have a sample tested

 

http://www.blackstone-labs.com/

[Doug_Scott]

Engine coolant/water are heavier than oil, so, if it is floating on the top of the oil in the drain pan it is not likely going to be engine coolant. You can also verify this by letting the vehicle sit overnight and then loosen the drain plug on the oil pan until it starts to leak. If there is coolant in the oil, it will be the first out of the pan when the drain plug is loosened. If you see drips of coolant first, then you have a leak of coolant into the oil. This can be a number of things, a few of which do not require the engine to have been overheated to cause the leak.

 

You will only see the milky appearance if there is sufficient water/coolant in the oil to actually be pumped through the oil passages, or whipped by the crank. Faulty PCV system can cause this condition in the winter if the engine is never fully heated up, and is used for short trips only. That is not coolant though, it is simply condensation. Generally changing the oil, then driving it for a very long trip will remove condensation by boiling the water out of the very hot engine oil. This does not appear as orange foam normally.

[wnyfarmboy]

I am getting a sample kit from blackstone.

[mainexile]

I think I may be having an issue with my 3.5 engine. The engine has 95K, has had the oil changed every 3000 miles and has never been overheated. I noticed that there was some orange type bubble scum on top of the oil in the drain pan the last time I changed oil. After a little while it disappeared. I changed the oil again over the weekend after 2400 miles and this time it was the same thing again only more than last time. It would appear the the coolant level in the reservoir has gone down just slightly. There is no build up or residue on the oil filler cap. The truck runs good and shows nothing unusual from the exhaust. The oil when drained cold looks fine with no milkiness, just the orange bubble type scum on top that disappears after a short while. Any ideas what the cause or cure for this would be? Any information would be greatly appreciated.

 

 

My '06 Canyon 3.5l had a similar problem a few years ago. Turns out there was a known head problem allowing coolant/oil cross contamination. Check with your dealer because mine was completely covered under a Technical Service Bulletin. They replaced the head, flushed both the oil and coolant systems, and it has been fine ever since. Good luck.