Strange coolant leak issue, any ideas?

[TheDoug]

So my 2018 platinum 4x4 has done this a total of three times. Once over a year ago an twice within the last three months. I get home, park it and come back hours later (or overnight) and there is a puddle of coolant on ground. It seems to dump a certain amount and then it stops. I fill the reservoir and drive and the level stays constant until this thing happens again.

The puddle appears to be coming from the middle skid plate, maybe near the heat exchanger for transmission?? Never get a good look because of all the skid plates.

Anyone come across this before?

Edit: attached puddle size pic

 

[professorfrey]

I have this same problem with the same vehicle, except mine is now leaking daily and quite a lot. Following this thread in hopes that someone has an answer. I've had the water pump and thermostat replace and it only seems to have gotten worse.

 

[TheDoug]

I have replaced the thermostat as well and it's not coming from that.

Is your leak toward the front of vehicle or more middle where engine and tranny meet?

 

[professorfrey]

I believe more toward the front. It's hard to tell where it's coming from because the fluid slides down through who-knows-where and then drips to the ground right around the area where the oil filter is located. I don't really know part names, but there is an iron shield on the very bottom of the truck and that's where it's dripping from.

Another thing that I find strange is that something it just doesn't leak. Like I can drive it for 10 minutes and park it and have nothing. Then later in the day, I'll drive a similar distance, park it, and and discharges over half of the reservoir.

 

[TheDoug]

Sounds like it's the same spot... Metal shield with the little square cut in it...

Luckily mine is not dumping that much but it's the same scenario... Drive for 6 months no issue... Then one day I park and it dumps. So strange

 

[GlennSullivan]

Could be cracked or leaking hoses going to the turbos or heater core. Doug you are going to need to temporarily remove those skid plates to find.

Professor you may have to remove the soft covers under the engine to find your leak.

Read this thread. Solution starts at post 6

Bad Radiator Cap? / Coolant Disappears

I encountered a coolant disappearing issue with my 2019 Expedition Max with 50,000 miles. I routinely check my fluids, and two weeks ago, I noticed the coolant reservoir was low and had to add about a quart of coolant. Today, I checked it again, and to my surprise, the reservoir was almost...

www.expeditionforum.com

 

[TheDoug]

Good info on the video. Gives me some places to look but mines so weird that it doesn't leak all the time. I feel like the tech in video is saying these problems spots just leak constantly when the wear out.

 

[bobward757]

Have you had the Shop do a pressure test yet? If it’s the fittings on the hoses that go into the radiator pressure test will show those instantly.

Good luck. Keep us informed

 

[Jerald Cook]

I had a leak in the coolant tube that connects to the driver's side turbo. Could be dripping down the turbo/exhaust and migrating from the actual source of the leak.

 

[md540i]

I didnt have time to look at that link yet, but I had a very similar issue with my 2018 Exp Max Limited.

Mechanic told me that it was a cooling pipe to the turbo leaking, there was a small crack in the pipe...the pipe is about $700 or so but the issue is that you basically need to pull the engine in order to replace this pipe as it is one contiguous y pipe that feeds both turbos from underneath the motor.

He suggested to sell the truck asap. To be honest I was looking to replace the vehicle anyway as I had about 60k miles and was having other issues with it. So that's what I did, he put sealant in the cooling system and I traded it in on a new 23 Exp Max Platinum leftover that I got a really good deal on.

Side note, found out the hard way that the 23 platinum's are missing a bunch of features due to supply chain issues, the Multicontour seats, kick to open tailgate, auto park and a few others.

Anyway just wanted to report my experience, luckily I was already on the fence for replacement so it wasn't a huge issue for me. Hope you have better luck.