Coolant level slowly going down and strange smell in engine bay.

Truckdriver

Well-known member
🪙 Founding Member
Joined
Jan 11, 2021
Messages
88
Reaction score
53
Location
Gulf Breeze Florida
Anyone having issues with slow coolant loss.

I’ve got about 33,000 miles on the Jeep currently and ever since it was new, I have had to add small amounts of coolant from time to time. Thus far I have probably used about a half of a gallon, and there are no visible leaks.

On another note, the engine seems to have a slight coolant smell, and at other times a slight electrical smell of which neither I can pinpoint.

Took it to the dealer and this is the response I got…🤷🏻🤷🏻 (Shocker)

Any thoughts out there?
 
The coolant expansion tanks have leaked on a few at the seam but you’d probably notice that. If you smell it in the exhaust and there’s white smoke it’s likely your head gasket.

They should pressure test the system and see where it’s leaking. If it is your head gasket you’ll eventually know or grenade the engine. Find another dealer if yours is useless.
 
I agree with Robr651. Get it documented prior to warranty lapse and/or buy the Mopar warranty from Granger.

VTW,You still have an H1? The early turbo ones had major coolant leaks in #8!!
 
Anyone having issues with slow coolant loss.

I’ve got about 33,000 miles on the Jeep currently and ever since it was new, I have had to add small amounts of coolant from time to time. Thus far I have probably used about a half of a gallon, and there are no visible leaks.

On another note, the engine seems to have a slight coolant smell, and at other times a slight electrical smell of which neither I can pinpoint.

Took it to the dealer and this is the response I got…🤷🏻🤷🏻 (Shocker)

Any thoughts out there?
It’s most likely your expansion tank like Robr651 mentioned. I’ve had quite a few cooling issues with mine and one having to replace the coolant expansion tank. If you unbolt it from the metal bracket you should have your answer if there is dried up coolant under it. If it’s not making its way to the floor it’s most likely that.

Mine is currently in the shop getting a cracked radiator replaced 🤷🏼‍♂️
 
I’ve noticed the same and topped off coolant twice so far. My coolant reservoir has no leak and no leak in the lines. Make sure to check the level when it’s COLD. In my case I consider it’s due to slow evaporation. It was lower than the MIN mark at COLD when I did top off for the first time at 8k, second time just added a few ounces at 14k.
 
Last edited:
I agree with Robr651. Get it documented prior to warranty lapse and/or buy the Mopar warranty from Granger.

VTW,You still have an H1? The early turbo ones had major coolant leaks in #8!!
Yeah…got it documented already. Just wondering if I’m alone.
I was lucky to get my Hummer outside of the VIN numbers that had the issue.
Actually converted it over to run on vegetable oil and had great success with that. Made it our economy car😆
Put about 80K miles on veg without a hiccup 🙌
 
It just seems weird that there are no leaks…no presence in the exhaust. (Smell or smoke).
My engine bay has never smelt like a “new car”, but it also doesn’t smell overly like coolant…it’s a smell I’ve never smelt before, and I’ve always been a gearhead.
A Buddy had mentioned that there have been some “not so obvious” leaks on the SRTs. I’ll follow up with him and let y’all know.
Stand by….🤔
 
It just seems weird that there are no leaks…no presence in the exhaust. (Smell or smoke).
My engine bay has never smelt like a “new car”, but it also doesn’t smell overly like coolant…it’s a smell I’ve never smelt before, and I’ve always been a gearhead.
A Buddy had mentioned that there have been some “not so obvious” leaks on the SRTs. I’ll follow up with him and let y’all know.
Stand by….🤔
Check the cap for the expansion tank. It may have failed
 
Timely thread. I checked all of my levels for the first time yesterday and both my coolant and power steering fluid were significantly low (power steering reservoir was empty). I picked up the proper liquid gold at the dealer today and as I filled the coolant reservoir tonight it leaked right out at what I am pretty sure is the area of the seam. Off to the dealer for my first warranty item.
 
Funny enough my coolant level seems to be going down very slowly. I've had the dealer add some a few months ago and now it's down again. It's hard to see where it's leaking from. I guess I'll have to schedule a dealer visit as well.
 
Funny enough my coolant level seems to be going down very slowly. I've had the dealer add some a few months ago and now it's down again. It's hard to see where it's leaking from. I guess I'll have to schedule a dealer visit as well.
I had a similar issue, turned out to be a faulty reservoir cap. $25 part (covered under warranty by the dealer).
 
.

What’s the deal with the faulty coolant expansion tanks?

Is it only certain years? Was there a recall or bulletin? If no problem yet, would it be wise to replace to avoid a potential mess in the future?

Would like to avoid leaked coolant on this great looking 392 if possible…

.
 
.

What’s the deal with the faulty coolant expansion tanks?

Is it only certain years? Was there a recall or bulletin? If no problem yet, would it be wise to replace to avoid a potential mess in the future?

Would like to avoid leaked coolant on this great looking 392 if possible…

.
No they all have the same tank. It’s a two part tank and some leak at the seam. I did notice that mine was rubbing at the seam where it mounts to the bracket. There’s two foam strips that run along the bottom and up the side of the tank and stop near the seam to help hold it in place and I’d assume to prevent rubbing. One of mine came loose. Something to look for. It was easy to put back in place.
 
  • Like
Reactions: SKT
There is a TSB that addresses a problem with the coolant overflow bottle seam. It only covers about 3 months in late 2022 though.
 

Attachments

  • Screenshot_20240220_072703_Drive.webp
    Screenshot_20240220_072703_Drive.webp
    91.4 KB · Views: 65
There is a TSB that addresses a problem with the coolant overflow bottle seam. It only covers about 3 months in late 2022 though.

Thanks for sharing! The date range is interesting. I currently have a low-mileage early ‘21 model and while it does not show any visual signs of leaking, I sure would like to avoid it if possible.

Has anyone replaced their tank as a preventive measure?
 
I've been waiting for an updated coolant reservoir from Mishimoto or any other company for an aluminum reservoir , hopefully they come out with updates hoses and radiator too
 
Speaking of fluids. What power steering fluid does the 392 take? I would like to order off Amazon if possible.
 
Speaking of fluids. What power steering fluid does the 392 take? I would like to order off Amazon if possible.
68088485AB I believe that’s the correct one and yes they sell it on Amazon
 
I'm about 38K miles on this 2021. Noticed on recent trip that coolant was slightly below minimum line on the reservoir. Watched temps, and I never went above 220 on a day of offroad, and a day of highway driving. 210 to 215 the average, but I did see 219/220. Strong coolant smell from vents in vehicle, ie when running heat. Visual inspection showed no apparent leaks at the tank seam or hoses/connections. FWIW, there was a very distinct sloshing noise behind the dash, which I understand is heater core air/fluid interacting.

Brought to my dealer. A day later, service advisor states that they pressure tested over night, and again the following morning after getting the engine hot. Never lost pressure, zero pressure loss. Was told they topped up the coolant. Quick inspection on my way out from dealer - clean work, still no evidence of leaks around tank/hose/connection. The level was higher, right between min and max. Ran the heat on the way home, still getting a massive coolant smell. This morning, the coolant level is back just below minimum, but still not seeing evidence of leak. Service advisor tried to explain something about - natural loss over time, air in the system, can cause odor with no "leak." Is that true? I bought mopar coolant , will top up tonight. Maybe the system still has air, and needs burping...ie maybe their top up didn't get me to full/full (?). Might change the cap that folks are describing as culprit...though not seeing indicators that mine is 'bad.' What are indicators of bad cap?

Thanks for any insights.
 
I'm about 38K miles on this 2021. Noticed on recent trip that coolant was slightly below minimum line on the reservoir. Watched temps, and I never went above 220 on a day of offroad, and a day of highway driving. 210 to 215 the average, but I did see 219/220. Strong coolant smell from vents in vehicle, ie when running heat. Visual inspection showed no apparent leaks at the tank seam or hoses/connections. FWIW, there was a very distinct sloshing noise behind the dash, which I understand is heater core air/fluid interacting.

Brought to my dealer. A day later, service advisor states that they pressure tested over night, and again the following morning after getting the engine hot. Never lost pressure, zero pressure loss. Was told they topped up the coolant. Quick inspection on my way out from dealer - clean work, still no evidence of leaks around tank/hose/connection. The level was higher, right between min and max. Ran the heat on the way home, still getting a massive coolant smell. This morning, the coolant level is back just below minimum, but still not seeing evidence of leak. Service advisor tried to explain something about - natural loss over time, air in the system, can cause odor with no "leak." Is that true? I bought mopar coolant , will top up tonight. Maybe the system still has air, and needs burping...ie maybe their top up didn't get me to full/full (?). Might change the cap that folks are describing as culprit...though not seeing indicators that mine is 'bad.' What are indicators of bad cap?

Thanks for any insights.
They did a pressure test on mine to identify the leaky cap. So if they did that on yours probably not the cap. The coolant levels do fluctuate based on the temp of the coolant so it will be lower when the vehicle is not warmed up. That wouldn’t account for the smell you are experiencing though.
 

Create an account or login to comment

Join now to leave a comment enjoy browsing the site ad-free!

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Latest Discussions

Back
Top