Frothy brown foam in oil?

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Grand_Wag_85
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Frothy brown foam in oil?

Post by Grand_Wag_85 »

I have a 2012 JK and just did an oil change on it and noticed a brown froth on the dipstick when I checked the level before the change. After dumping the oil there was a blatant brown frothy foam on the surface of the old oil. It was a completely different color than the oil that came out, almost a chocolate color.

I've always done all my own oil changes but I can't say that I have ever noticed anything like this.

Is this a sign of anything amiss up in the engine? There is ticking, chattering and spark knock which Chrysler claims is completely normal for these engines, even with 20,000 miles on them. I do know about the cylinder head recall but they will not do anything about it until it throws codes.
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WaggyGuy
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Re: Frothy brown foam in oil?

Post by WaggyGuy »

Kind of sounds like water or coolant in your oil. Check your coolant and make sure you aren't losing any. You can also pull the radiator cap (careful doing that) with the engine running and see if your coolant is bubbling.

I had that happen on an older Jeep. The top of the oil line on the dipstick was frothy/bubbly. I only drove it short distances each day (maybe a quarter mile total), which caused condensation to build up because the engine never got hot enough. Once I started driving it more it had a chance to heat up and burn off the condensation and the problem went away.
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Stuka
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Re: Frothy brown foam in oil?

Post by Stuka »

Was it overfilled? Foam normally means the oil is getting churned up.

But the color does sound like water or coolant. When you drive it, how long do you normally drive it? If the engine doesn't get fully warmed up it can build up a lot of condensation in it. But it may be coolant too.
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Tatsadasayago
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Re: Frothy brown foam in oil?

Post by Tatsadasayago »

The consensus is that if the oil itself hasn't turned into a chocolate milkshake, what you are seeing is likely condensation from the interior of the crank case settling on the oil. The froth on the dipstick is is very common on engines that see a lot of short runs. Engines that have Pennzoil, Quaker State or any other Pennsylvania crude that has a higher than usual parrafin content when used in engines that don't see long (4-8 hours) run times tends to create a cream-colored 'cottage cheese' sludge buildup in the pan, lifter galley and top of the cylinder head(s).
A hot oil change and a good long highway run will do wonders.
A radiator combustion gas test will tell you if you've got a head gasket leak if things get worse.
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Grand_Wag_85
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Re: Frothy brown foam in oil?

Post by Grand_Wag_85 »

My shortest trips are about 20 minutes. Often times the Jeep sits for a week then drive it all over for a few days, no real set pattern. I do a TON of HWY miles, changed the oil on Friday and already clocked 1,000 miles. In the year I've owned it I've put kn 20,000 miles.

Using Mobil1 5W-30 and changing every 3K to keep the warranty goons at bay.
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Re: Frothy brown foam in oil?

Post by Stuka »

After that 1k miles, how does the oil look?
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Re: Frothy brown foam in oil?

Post by Grand_Wag_85 »

Clean and clear with no froth.
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csuengr
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Re: Frothy brown foam in oil?

Post by csuengr »

Just make sure the chocolate milk isn't also in the coolant.
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Re: Frothy brown foam in oil?

Post by Grand_Wag_85 »

csuengr wrote:Just make sure the chocolate milk isn't also in the coolant.
Will do
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Re: Frothy brown foam in oil?

Post by candymancan »

Pics would be nice.. froth like foam is usually due to overfilling..

If the oil is like a icecream milk shake consistancy ( like a coke float and a chocolate milk color then its coolant in the oil
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1990 Jeep Grand Wagoneer 155k
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will e
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Re: Frothy brown foam in oil?

Post by will e »

Have you lost any coolant?
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Re: Frothy brown foam in oil?

Post by Grand_Wag_85 »

I'll have to take a look.
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Re: Frothy brown foam in oil?

Post by candymancan »

Coolant loss can come from a lot of areas though.. My 90 is leaking from the intake in the back.. both back bolts... I need to tackle that when it gets warm. Its enough to show a loss of coolant in the reservoir over a period of time. Kinda weird how it leaks outside but not inside. I hear its an issue on these engines for coolant to leak out the rear bolts
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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