Help Identifying these coolant part(s) on 2017 Ford Expedition XLT 3.5L V6 with EcoBoost

Hi Everyone,

Our 2017 Expedition XLT 3.5L V6 with Eco Boost with roughly 90k-95k in miles. When we took the car in for some recall work, the technician noticed there was a coolant leak, and wanted to bill us for 2 hours to try to find it. We aren't noticing any overheating and the coolant level looks good, so I'm guessing this is a slow leak. I'm pretty sure I found it in 5 minutes, on the Engine Coolant

I know this forum is filled with people who know far more about these vehicles than I do. Before I start dropping money on attempting to replace these parts, I want to see if others:
A) Agree that this does look like a culprit
B) Is this the upper hose I'm seeing in this photo coming off the expansion tank
C) What is that elbow piece in the photo with what looks like a worn gasket


If possible, I would prefer to just do the work myself

Rev1024 said:

Hi Everyone,

Our 2017 Expedition XLT 3.5L V6 with Eco Boost with roughly 90k-95k in miles. When we took the car in for some recall work, the technician noticed there was a coolant leak, and wanted to bill us for 2 hours to try to find it. We aren't noticing any overheating and the coolant level looks good, so I'm guessing this is a slow leak. I'm pretty sure I found it in 5 minutes, on the Engine Coolant

I know this forum is filled with people who know far more about these vehicles than I do. Before I start dropping money on attempting to replace these parts, I want to see if others:
A) Agree that this does look like a culprit
B) Is this the upper hose I'm seeing in this photo coming off the expansion tank
C) What is that elbow piece in the photo with what looks like a worn gasket

View attachment 74945
If possible, I would prefer to just do the work myself

Click to expand...

My 2015 leaked at that point.

The coolant reservoir nipple has a metal insert, and the outer plastic cracks.

The reservoir is called a degas bottle.

Do you have an extended warranty, as mine was covered under the Ford Premium Care service plan. Several other coolant hoses also leaked at the connectors, and were also replaced. I did not do the work.

Unfortunately, no extended warranty. You’re right that is the degas bottle. I didn’t find any other signs of leaking anywhere else. I just have to make sure I get the right hose, and figure out what that elbow and gasket are.
I appreciate the response.

Very common point of failure are the coolant lines going into the turbos. If you are lucky and only have a problem at the T connector then I’d suggest using Tasca online for Ford/Motorcraft parts. Hop on YouTube and you’ll find a video on replacing the expansion tank and many videos on replacing the turbo coolant line connectors.
I’ve built a library of YouTube videos but a great starting point is Fordtechmakulico’s channel.

This guys a bit slow in his delivery but you’ll get an idea of the parts that are involved.

I have/had this exact issue and previously paid a Ford Dealer to diagnose the leak. Even with a pressure test they were unable to find the source and told me (even wrote it on the service ticket), "turbo'd engines burn coolant."

At the next oil change which I decided to do myself, I found my fitting at the reservoir looking exactly like the picture posted above. My leak was at the factory plastic crimp and not the oring quick connection side. I replaced the hose with an OEM hose wanting to keep everything factory as the truck was only a few years old. That hose lasted 10k miles and is now leaking at the oring connection to the reservoir.

I still have not installed it, but I've given up on the OEM ford parts and ordered the following kit from Pegasus which eliminates to crap plastic quick connect and uses a silicone hose, aluminum barb adapter and hose clamps to resolve the issue. There are other kits available on amazon that seem to be cheaper now.