jku DJ

hey i am having the same EXACT issue with my jeep. guess i should have searched before posting. but anyway did you find the source of your leak...?!?!?!??? i bought my 2015 in feb of 2015 also... go figure

DJ1

It's pretty much been 1 (or a combo) of the following:
1. Bad water pump
2. Bad radiator
3. Bad thermostat
4. Cracked oil/coolant cooler housing

These are all components than can be replaced under the power train warranty...

NO-ROADS

My coolant was vanishing too. Finally tracked it down when there was coolant residue on the bottom driver side of the radiator. Local Jeep dealer replaced the radiator under warranty. Said they had seen a few like that.

Cmk4ua

I have the exact same problem. I've already had the radiator replaced under warranty. I have a 2014 Wrangler Unlimited Sahara. Radiator was replaced two months ago. Dealer had coolant reservoir filled above the max line and now there is about an inch and a half of coolant left. I have another appointment Thursday at the dealership for them to look at it.

nosnhoj1

Same thing with my '14 and it ended up being a cracked thermostat housing.

702Rubi

I just got my 2015 JKU back from a different Las Vegas dealer. Among other things, I asked them to again look at this coolant issue. Because the reservoir was practically empty. There was just a little bit of coolant visible way down in the bottom, far below the min level line.

They said they didn't see any sign of a leak. And according to the paperwork, they did a pressure test (again), no problem found.

But according to the tech, the coolant evaporates over time, and that is why the level in that tank drops. Really? I thought it was supposed to be a closed system? Also, I've owned a variety of vehicles over the years, none of them have lost coolant the way this one does.

Furthermore, according to him, that tank is only an overflow tank, not a reservoir. If that's true, then why are there min and max level marks on it?

I think they're trying to BS me, what do you think?

Anyway, in addition to the other needed repairs (replaced leaking rear shock and leaking hardtop liftgate strut), they topped it up for me again. Hopefully with the correct coolant.

Rednroll

It sounds to me like you're being BSed. I had the same coolant in my 2009 until I reached 100K miles when I started to identify hard to find small leaks from both the radiator and lower intake manifold gasket.

I had to purchase a pressure tester to find mine. It might be worth the investment and do the same rather than trusting the dealer. I would start by looking at the items DJ1 mentioned earlier.


As well, it is very common for the heater core to leak around the elbow joints in our JKs, so it might be worth feeling up around the passenger floor mat area to see if it feels wet at all. If it is, then your HC is leaking. The heater core is in the lower center dash area and the elbow joints are to the right. So that's the area you would find it wet, if it's leaking.

702Rubi

Wouldn't I smell it in the cabin? I've not noticed any dampness in that area.


BTW, I was just looking at the owner's manual, and found the following statement. Sure sounds to me like the cooling system is a sealed system...

"...Check the cooling system pressure cap for proper vacuum sealing by draining a small amount of engine coolant (antifreeze) from the radiator drain ****. If the cap is sealing properly, the engine coolant (antifreeze) will begin to drain from the coolant recovery bottle."

Edit: LMAO, it censored the word C o c k

702Rubi

Oh, and there's also this in the manual:

"The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine idling, and warm to normal operating temperature,
the level of the engine coolant (antifreeze) in the
bottle should be between the ranges indicated on the
bottle."

Rednroll

It's pretty common for the JK's to have radiator leaks from the end caps which are hard to find. The reason they're hard to find is because the pressure needs to be built up to push the end caps out for the leak to start happening. Then the coolant either blows out as you're driving or it drips into the skid plate or air dam under the radiator where it's not dripping on the ground. You need a pressure tester to find those type of leaks.

Also in my case I had a lower intake manifold gasket leak. I couldn't find that leak with a pressure tester, because the engine needs to be running and heated up for the manifold to start expanding due to heat and then exposing the leak. You will need to look closely and identify any coolant near the spark plugs. I found mine when the leak got larger and became obvious that coolant was leaking from the engine.