Coolant in oil!

rumbackd said:

My 2012 I-4 Colorado has the dreaded white slime on the dipstick!
Fresh oil 1,500 miles ago, 98,000 miles on the truck.
Is there anything else to check before I assume it's the head gasket?
Rummy - Kansas

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rumbackd said:

My 2012 I-4 Colorado has the dreaded white slime on the dipstick!
Fresh oil 1,500 miles ago, 98,000 miles on the truck.
Is there anything else to check before I assume it's the head gasket?
Rummy - Kansas

Click to expand...

Where are you located. It's winter up north. When an engine is shut down and cools off, condensation forms internally. If a vehicle is not driven long enough to allow that condensation in the engine to burn off, during subsequent engine operation, it can mix with the oil and cause the situation you describe. Before assuming that it is a head gasket, weather permitting, drive the vehicle for a period that extends well beyond the normal operating temperature.

If the word 'winter' has no meaning for you, disregard the above advice.

cart7881 said:

Where are you located. It's winter up north. When an engine is shut down and cools off, condensation forms internally. If a vehicle is not driven long enough to allow that condensation in the engine to burn off, during subsequent engine operation, it can mix with the oil and cause the situation you describe. Before assuming that it is a head gasket, weather permitting, drive the vehicle for a period that extends well beyond the normal operating temperature.

If the word 'winter' has no meaning for you, disregard the above advice.

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Thanks for the info! I first noticed this on my way home from Chicago for a Christmas visit. We drove 5 hours, spent the night, then found the slime when I checked the oil the next morning before driving 7 hours home. Upon checking the dipstick the following morning, it had considerably less slime. What you're saying adds up with what I'm seeing on the dipstick.

rumbackd said:

Thanks for the info! I first noticed this on my way home from Chicago for a Christmas visit. We drove 5 hours, spent the night, then found the slime when I checked the oil the next morning before driving 7 hours home. Upon checking the dipstick the following morning, it had considerably less slime. What you're saying adds up with what I'm seeing on the dipstick.

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This was the subject of much discussion some years ago. Most guys noticed the accumulation in the area of the oil fill cap., where it cools off quicker.

I Have an 06 colorado 2.8. Its had this white milky slime on the dipstick the 4 years Ive owned it. Doesnt ever seem to bother it. I plan to drop the oil pan next change and clean it out with a rag to remove it all. But it has no effect on the truck. after long drives it cleans up a bit.

I noticed a little bit under my oil cap too the other day. Based on the discussion that we have seen here, it is not a big deal. But there is no known resolution or fix, other than allowing the engine to warm up as much as you can.

When the weather gets cold and if you are doing only short trips, condensation does not have a chance to evaporate out of the oil and ends up as the milky white sludge on the dipstick and the oil cap. My 2005 also had a half working thermostat that would not allow it to get all the way to operating temp. I had the sludge for a couple of years before I changed it out. Now I only see it once in a while if the truck is only doing short trips in the winter time.

rumbackd said:

My 2012 I-4 Colorado has the dreaded white slime on the dipstick!
Fresh oil 1,500 miles ago, 98,000 miles on the truck.
Is there anything else to check before I assume it's the head gasket?
Rummy - Kansas

Click to expand...

Check the radiator! . I had a radiator failure where the radiator wall failed and allowed the mix of coolant and trans. fluid.

Thanks for the info! Do I check by looking in the radiator for the white slime?

Rummy

jcbcts said:

When the weather gets cold and if you are doing only short trips, condensation does not have a chance to evaporate out of the oil and ends up as the milky white sludge on the dipstick and the oil cap. My 2005 also had a half working thermostat that would not allow it to get all the way to operating temp. I had the sludge for a couple of years before I changed it out. Now I only see it once in a while if the truck is only doing short trips in the winter time.

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is there any chance this could also happen in the spring or summer. I have a canyon with the 2.8 and recently noticed the coffee oil you guys are talking about and im certain the head is fine. I drive only 7 mins to work every day and usually only let the truck warm up for a few seconds. It has rained a lot here recently so I'm hoping that could be cause enough for condensation to form

When its humid, sure its a possibility. The winter chill makes it more prevalent, but a cool night after a muggy day surely can cause condensation to form. Then that emulsifies with the oil, and you get the sludge. Do your due diligence and make sure your coolant is clean, and check out your oil next time you drain it. I bet your short commute and humidity are to blame.

Dragon08 said:

When its humid, sure its a possibility. The winter chill makes it more prevalent, but a cool night after a muggy day surely can cause condensation to form. Then that emulsifies with the oil, and you get the sludge. Do your due diligence and make sure your coolant is clean, and check out your oil next time you drain it. I bet your short commute and humidity are to blame.

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coolant seems fine. it must be from the humidity and short commute because it rarely reaches peak operating temp by the time I get to work. truck has ALOT of km. 350,000. my third week of ownership.

natesCanyon said:

coolant seems fine. it must be from the humidity and short commute because it rarely reaches peak operating temp by the time I get to work. truck has ALOT of km. 350,000. my third week of ownership.

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If your coolant level is not dropping then it’s probably just condensation like everyone says.

rumbackd said:

My 2012 I-4 Colorado has the dreaded white slime on the dipstick!
Fresh oil 1,500 miles ago, 98,000 miles on the truck.
Is there anything else to check before I assume it's the head gasket?
Rummy - Kansas

Click to expand...

I discovered this same issue on my 2009 GMC Canyon WT 2wd 4cyl (81,000 miles) over this past winter. I really assumed I had coolant in oil. Truck sat for a couple weeks and I drained a lil oil out - saw no signs of coolant in oil. A mechanic suggested dropping in a couple of those GM coolant sealant tabs just to be sure so I did. No signs of coolant loss. Was told most likely just condensation and maybe a thermostat issue. On the dash the temp gauge usually rides a lil below the 1/2 mark. Sometimes less than that on really cold days. I've also read in some forums that GM put in a 180 degree thermostat and that replacements now are 187 degrees. Not sure if this is correct, but looking at some replacement thermostats they are listed as 187 degrees. I can't find what replacement AC Delco thermostats are. They don't list the temp on those. Maybe someone else can elaborate on this.

I agree with the condensation diagnosis. Just try to drive the truck long enough, each time, for the engine temp to get rid of the accumulated moisture.

Although a defective thermostat could contibute to the issue, don't automatically replace yours, thinking it is bad. From the factory, most temp gauges will normally read about mid-range. Mine reads a bit below and is good. The sign of a thermostat stuck open will be when the temp gauge reads about 1/4 scale.

I think all GM approved thermostats for these trucks are set at 95°. That's what the thermostat in your truck should have had when it left the factory.

If you want to know which thermostats are correct for your truck, navigate over to rockauto.com

cart7881 said:

I agree with the condensation diagnosis. Just try to drive the truck long enough, each time, for the engine temp to get rid of the accumulated moisture.

Although a defective thermostat could contibute to the issue, don't automatically replace yours, thinking it is bad. From the factory, most temp gauges will normally read about mid-range. Mine reads a bit below and is good. The sign of a thermostat stuck open will be when the temp gauge reads about 1/4 scale.

I think all GM approved thermostats for these trucks are set at 95°. That's what the thermostat in your truck should have had when it left the factory.

If you want to know which thermostats are correct for your truck, navigate over to rockauto.com

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"I think all GM approved thermostats for these trucks are set at 95°. " .... that's either a typo or just way off. My Temp gauge is usually 1 to 2 marks below the 1/2 point depending on outside Temps. It has never reached the 1/2 mark.

LOL! Another one of my Senior Moments!! You're correct, should have been 195°. I'll have to do a better job proofreading before I hit 'Post'