2015 Expedition 3.5 EcoBoost – slow coolant leak at driver-side turbo, looking for input

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

H60John

Member
Joined
May 20, 2026
Posts
6
Reaction score
1
Location
Oklahoma
Hey all, wanted to lay out my situation and see if it lines up with what others have experienced.

Truck: 2015 Expedition Platinum, 3.5 EcoBoost, ~121k miles.

Background: Bought it ~7 weeks ago. Had a timing cover reseal / rear main / oil return pipe done right after purchase (warranty work). An oil drip showed up the day that job finished but has since resolved – no more oil.

Current issue: Now I've got a COOLANT leak (orange Motorcraft, bitter/watery) weeping at the driver-side turbo area. Symptoms:
- Only shows up after the truck is warm / driven, dries up overnight
- Drips a small contained spot on the driveway (~fist-size an hour after a drive), not a puddle or trail
- Coolant reservoir is holding steady
- NOT overheating, temp gauge normal
- Visible orange staining + a fresh droplet at the fitting near the turbo

Diagnosis so far: Dealer says left turbo internal seal, $1,833 to replace the turbo. Christian Brothers quoted $1,775 (Ford reman turbo, ~$700 labor) but that was off the dealer's diagnosis, not their own look. I have NOT confirmed whether it's actually the internal seal vs. the external coolant line/jiffy fitting/O-ring – from what I'm reading those clip-in fittings are the usual culprit and a much cheaper fix.

My plan (can't afford the repair right now, looking at ~a year out):
- Monitor reservoir level (check cold) + watch temp gauge
- Keep a jug of coolant in the truck, top off as needed
- Avoid long hauls / towing where I can (typical drive is ~90 min)
- Pay for a cooling-system pressure test ($80) to confirm seal vs. line before committing to any repair
- Possibly upgrade to AN/braided lines when I do fix it so I'm not chasing it again

Questions for those who've been here:
1. Does a slow weep like this realistically hold for months on careful monitoring, or did yours accelerate fast?
2. Anyone have it diagnosed as "internal seal / replace turbo" when it turned out to just be the external fitting/line?
3. For ~90-min highway drives, anything beyond "full before you leave + watch the gauge + carry coolant" you'd recommend?

Thanks in advance – trying to nurse it safely until I can afford to do it right.

IMG_8767.jpeg
 

17expi

Well-Known Member
Joined
Apr 17, 2026
Posts
67
Reaction score
15
Location
Mt Shasta Ca
I agree with your "plan" except for the $80 coolant check, which won't tell you anything you don't already know, and braided lines won't do anything other than make your wallet lighter. It's probably one of those little O rings in one of those tubes that you can fix yourself. Pretty common leak and nothing to worry about.
 
Top