Unexplainable engine coolant loss

Hello
I'm new to the forum and have a puzzling question for the group. I purchased a new 2024 Grand Cherokee with a 3.6L engine in April 2024. I brought it in to the dealer twice for free oil changes and tire rotations. Both times I have pointed out to the service tech the coolant level in the expansion tank is one inch below the min level cold. Prior to taking it in I found no evidence of external leaking. The engine oil looked okay so no internal leak. The service tech topped off the coolant both times. I had them perform a coolant system pressure check on the second visit and the system held pressure and no leaks were found. Today the coolant level is 5/8" below minimum spec and it's been 1700 miles since it was serviced. I've owned dozens of cars in the past and never witnessed this phenomenon. Any ideas what's going on?

 

Are you detecting any antifreeze aroma? The 3.6 in my 2012 JK was doing that and it was a left side head gasket seep. How long did they run the pressure check? Did I mention I developed nothing but absolute disdain for that engine?

 

Thanks for the reply MT. When I open the hood after a drive, it does have a warm sweet aroma, probably coolant. I don't know how long they ran the pressure test but I was at the dealer for 2 hours. I'm heading to Florida on Saturday for 2 months and will run my own overnight pressure test when I get there. The next door guy is a retired master mechanic still doing neighborhood jobs so he'll have the tools I need for further analysis.
Today, I pulled the oil dipstick and the liquid level was one inch above the max mark!! The texture and color looked okay, no chocolate milkshake. I took it to the dealer who did the oil changes. the Service Manager was certain it wasn't glycol mixed in by looking at the stick. He opined that the tech overfilled it. They use a gun to fill the crankcase with oil and obviously do not check the stick after oil fill. I suggested they pull an oil sample and get it checked in a lab for evidence of glycol but they refused.
My 3.6L engine is 12 years newer than yours so I hope they have fixed the problems from the early years. Care to share specifics regarding your disdain?

 

I have a 2025 GC Limited with 13,000 miles on it and the coolant level dropped about an inch in the last month. I topped off and it is down a half inch.
It is due for an oil change and I will inquire with the dealer when I bring it in.
I had many reservations about this engine and Jeep quality overall and hoping there is nothing to this

 

Be sure to log your coolant additions, dates, amounts, etc. and your interactions with the dealer so you have a history of this problem.

 

Good advice. Keep us informed of what you find
Best Regards