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Engine coolant?

ismail1724

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I was checking the fluids on this 2025 jlu wrangler rubicon I recently purchased and noticed that this black reservoir with black cap right next to the clear reservoir one might be a little low on fluid. I think this is the engine coolant reservoir, can someone verify this? I don't want to add incorrect fluid. Is this dangerously low or nothing to be worried about?

Jeep Wrangler JL Engine coolant? IMG_8782


Jeep Wrangler JL Engine coolant? IMG_8781
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Odyssey USA

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Looks low. For a safe bet, stick to the Mopar 50/50 coolant. Last year it was about the same price as every other option. Wrong one would be bad news.

All, I thought the black reservoirs got the dipstick style cap to read the level? At least on my 19 2.0 it was that way.
 
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ismail1724

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Looks low. For a safe bet, stick to the Mopar 50/50 coolant. Last year it was about the same price as every other option. Wrong one would be bad news.

All, I thought the black reservoirs got the dipstick style cap to read the level? At least on my 19 2.0 it was that way.
Yea you're right it does have the dipstick style cap and it came out dry as well. Thank you!
 

roaniecowpony

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Don't bother chasing down the Mopar coolant at this point. You likely have a leak for a 2025 to be that low on coolant. The main thing is to not drive it when it's that low. The main thing is to not drive it when it's that low.

Once more..... Don't drive it without putting something in it.

Since you're likely to be having the coolant tank replaced, just put distilled water in it.

Fill it to the "FULL" mark and drive it to your mechanic/dealer, tell them how much you had to put in, approximately. Watch for overheating on the way to the mechanic/dealer. If it overheats, stop immediately.
 
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ismail1724

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Don't bother chasing down the Mopar coolant at this point. You likely have a leak for a 2025 to be that low on coolant. The main thing is to not drive it when it's that low. The main thing is to not drive it when it's that low.

Once more..... Don't drive it without putting something in it.

Since you're likely to be having the coolant tank replaced, just put distilled water in it.

Fill it to the "FULL" mark and drive it to your mechanic/dealer, tell them how much you had to put in, approximately. Watch for overheating on the way to the mechanic/dealer. If it overheats, stop immediately.
The thing is I actually purchased this vehicle in Utah and drove it all the way to California which was around 1,000 miles or so and have been driving it for a week. I haven't had any issues with overheating, but it seems like a common problem with these is leaking. I just purchased some of the mopar coolant 50/50 off amazon. I think I will top it off and keep an eye on it to see if it goes back down then I will take it to the dealer.
 

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roaniecowpony

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The thing is I actually purchased this vehicle in Utah and drove it all the way to California which was around 1,000 miles or so and have been driving it for a week. I haven't had any issues with overheating, but it seems like a common problem with these is leaking. I just purchased some of the mopar coolant 50/50 off amazon. I think I will top it off and keep an eye on it to see if it goes back down then I will take it to the dealer.
Look around the seam of the tank for the dried coolant residue. You can run your fingers around and under the tank and look for it on your hands.
 

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Usually it would be obvious if the coolant tank seam had crapped out, that one looks pretty clean. Check the hoses with heat shield on them by running your hand over them, I had one leaking that didnt drip but once i touched the heat shield i could feel coolant.
 

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I hate dealerships. But, I’m with @roaniecowpony on this. You’re under warranty, take it to the dealership so things are documented. My radiator split at under 18,000 miles offroad without warning. I am pretty ridiculous (paranoid?) about doing my own maintenance, so as we were doing a steep climb I thought, oh that older Jeep ahead of me smells like it’s overheating. Well it was the newer Jeep I was driving.
 

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Well this at least solves the mystery of how ya'll were checking coolant levels on those black reservoirs.

What is the reasoning behind some having black and others having clear? Clear is much easier to check but does the black plastic resist heat more? Is that why?
 

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Wow, my coolant (overthrow) tank is clear, not black. WTH?? Do this: buy a gallon of (ONLY) this coolant, picture. Comes in pre-mix ready to use, or concentrate, mix with 50% distilled water. The premix is great to easily top off your coolant level, "occasionally". If you have to add coolant frequently, like every month or so, you have a leak...

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Well this at least solves the mystery of how ya'll were checking coolant levels on those black reservoirs.

What is the reasoning behind some having black and others having clear? Clear is much easier to check but does the black plastic resist heat more? Is that why?
Yes, because it's close to the turbo
 

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This is standard practice for the Jeep 2.0l. Just check and refill at each oil change.
 

kah.mun.rah

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It might just be the light in the photo but if your coolant looks more like chocolate milk than grape Kool-Aid, you might be looking at a blown head gasket.

Any bubbles on your engine oil dipstick?
 

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Coolant mixed with oil makes a chocolate milk looking liquid. Oil in the coolant tank will float on top of the coolant.
 

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@ismail1724

In no particular order:

The black plastic tank that you ask about is the pressurized coolant reservoir for the 2.0T's primary cooling circuit. The cap should only be removed, and the fluid level checked and/or topped off, when it is cool to the touch. The tank is opaque because of the polymer chemistry that is required to manage the heat of the adjacent turbocharger assembly. This is why, for example, the same reservoirs on the V6-equipped Jeeps are clear.

Note the presence of a separate coolant reservoir, behind the driver's headlight, for the intercooler circuit. The coolant level in that tank, which is clear because there's no risk of heat damage from surrounding components, must also be monitored and maintained at the correct level.

Use only OAT coolant; the Mopar product is best.

You don't necessarily have a leak in the system at this time, unless you've confirmed the presence of a leak as evidenced by crusty deposits on the related hose fittings, the seam of the reservoir itself, and/or fluid accumulation under the vehicle. Any number of 2.0T owners, myself included, have occasionally had to add coolant until the level eventually stabilizes (as I have also experienced.) The conventional wisdom suggests that there is an underfill at the factory, after which the related air in the system needs to work itself out over time.

Top off the reservoir in your Jeep and monitor it. Consider reaching out to a dealer if you're unsure of anything.
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