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392 Coolant Mixing with Oil?

EugeneTheJeep

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Need some help from the forum since my dealer is struggling. At 6000 miles, I’ve had a slow coolant level drop for several weeks. Pressure test ok. No drips. Three times to the dealer, and they say it’s fine. Today the level was higher (!), and I saw this on the inside of the reservoir bottle.
Jeep Wrangler JL 392 Coolant Mixing with Oil? 04E7A895-6745-4BB0-8AD8-F7611082DC95
Jeep Wrangler JL 392 Coolant Mixing with Oil? BC971D05-0795-4469-9D8A-F544F39E086B

Is this oil residue? Does the oil on the dipstick look ok?
Jeep Wrangler JL 392 Coolant Mixing with Oil? 16AFFC5E-4535-4ECB-AFA6-744764AD502D
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EDIT: One more note. There is a smell of graham crackers above the radiator (when hot with the blower off). The dealer says that’s normal for this engine (392). This doesn’t seem right to me. Do others with 392s have a coolant smell above the radiator?
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SparkleTooth

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I seriously think these forums have turned us all into nervous wrecks when it comes to looking for problems. I highly doubt your coolant is mixing with you oil. Coolant levels will fluctuate +/- a small percentage especially with a high performance motor such as the 392. Looking under your oil filler cap. Do you see any white milky residue? If so you have a problem, and if not drive it and enjoy the thing
 

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This is what coolant mixed with oil looks like:

Jeep Wrangler JL 392 Coolant Mixing with Oil? 1661885983330


You are fine.
 

Steph1

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Coolant is somewhat of a problem, as I too find it going down. I've added a bit, and It seems like the Jeep will spit it out and is always at the seem between the lower and higher part of the coolant expansion tank.

As sparkletooth says, forums are turning owners into paranoiac freaks. I got rid of my 911 partly for similar reasons. You know, when watching a dream vehicle go with its new owner brings more relief than heartache, it says a lot about the seller's state of mind.

Drive it and have fun, start worrying when you see such things as the warranty is close to expiring
 
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EugeneTheJeep

EugeneTheJeep

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I seriously think these forums have turned us all into nervous wrecks when it comes to looking for problems. I highly doubt your coolant is mixing with you oil. Coolant levels will fluctuate +/- a small percentage especially with a high performance motor such as the 392. Looking under your oil filler cap. Do you see any white milky residue? If so you have a problem, and if not drive it and enjoy the thing
This is what coolant mixed with oil looks like:

Jeep Wrangler JL 392 Coolant Mixing with Oil? 1661885983330


You are fine.
I do have a problem. My coolant level has been steadily dropping over weeks. I’ve gone through half a jug refilling it. The loss is slow. There is a leak somewhere, and what’s in the photos of the reservoir is the only thing that looks unusual. I’ve never seen residue on the inside of the reservoir until today.

Not a ‘nervous wreck’, just looking for some help.
 

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EugeneTheJeep

EugeneTheJeep

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I've added a bit, and It seems like the Jeep will spit it out and is always at the seem between the lower and higher part of the coolant expansion tank.
You mean it’s steady at that level but won’t hold a higher level?

My reservoir was almost empty when I looked at it the first time.
 

Remorseless

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I do have a problem. My coolant level has been steadily dropping over weeks. I’ve gone through half a jug refilling it. The loss is slow. There is a leak somewhere, and what’s in the photos of the reservoir is the only thing that looks unusual. I’ve never seen residue on the inside of the reservoir until today.

Not a ‘nervous wreck’, just looking for some help.
If you're losing that much coolant, really only a few places it could be going - on the ground from a leaking hose/fitting, out the tailpipe, or in with the oil. Check around the engine and hose fittings for dried purple/pink-ish crust. If nothing, drain the oil and check to see if that's looking like a milkshake. I assume it's not going out the tailpipe since you'd notice pretty easily if you're smoking like it's leaking into the combustion chamber.
 

SparkleTooth

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I do have a problem. My coolant level has been steadily dropping over weeks. I’ve gone through half a jug refilling it. The loss is slow. There is a leak somewhere, and what’s in the photos of the reservoir is the only thing that looks unusual. I’ve never seen residue on the inside of the reservoir until today.

Not a ‘nervous wreck’, just looking for some help.
The residue you are seeing isn’t oil/coolant mix residue. That is pretty normal looking, although if you are consistently burning through coolant then I suppose there is the potential for a leak. Smell around the outside and underneath of your motor after driving it a while. If you smell a sweet, syrup type smell then perhaps you have a leak. I don’t think it is in your oil though unless you potentially have blown a head gasket or something which you would know.
 

BDinTX

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It probably wouldn't hurt to send an oil sample off for an analysis for peace of mind.
There seems to be a high occurrence of the 2.0T cooking off coolant. I'd imagine these would be pretty hot under the hood too.
 

Steph1

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You mean it’s steady at that level but won’t hold a higher level?

My reservoir was almost empty when I looked at it the first time.
Yes, even if I put some more in it, seems like the jeep spits it out and goes back to that middle seam. Coolant in the oil makes a milkshake like hazy mixture. As for yours being almost empty when you noticed it the first time, maybe the system wasn't bled properly in the first place. Just keep monitoring it.
 

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Remorseless

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It probably wouldn't hurt to send an oil sample off for an analysis for peace of mind.
There seems to be a high occurrence of the 2.0T cooking off coolant. I'd imagine these would be pretty hot under the hood too.
With the 2.0T Jeep or a line worker wasn't putting Loctite on some bolts holding a flange for the water pump. They back out and you lose coolant, sometimes slowly or sometimes all once. Though, I'm sure some of the 2.0s out there are just cooking it, but a lot of it is around the TSB for loose coolant flange bolts. There's also one for hose clamps.
 
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EugeneTheJeep

EugeneTheJeep

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Smell around the outside and underneath of your motor after driving it a while.
When hot, motor and fans off, the top of the radiator smells sweet. The dealer says that’s normal for these engines. I’m not sure if that’s true or not. No smells anywhere else.
 
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EugeneTheJeep

EugeneTheJeep

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maybe the system wasn't bled properly in the first place
Good idea, but the dealer did a 2 hour bleed. The coolant level was still dropping after that.
 

dcmdon

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I'm not saying that you don't have a leak. But it doesn't look like you have coolant getting into the oil and vice versa.

If you are that worried about it, go on Blackstone's website and get a free test kit and send some oil in for analysis.

On the plus side, you've got 60,000 miles to figure this out.

I've got a strange clunking coming from my front axle. I've decided to just wait it out. I'll figure it out eventually and if if it fails, then the diagnostics are done.
 

supermike

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to be honest, like I said it before, unless it's black & white, you can physically see it leaking, dripping, broken, missing or have a constant error code. They are unlikely to Warranty repair it. It is the way it is. Sadly that's how small little things turns into catastrophic failure, but for the sake of warranty policy.

I'm having transfer case problem and couple trip to the dealer already...no fix yet....Problem it not consistence, I will either drove the tcase to explode or straight to dealer while the light is on without restarting the engine, which, still gonna kill the tcase......
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