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

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H60John

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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

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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.
 

99WhiteC5Coupe

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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.

View attachment 87300


I bought a new 2015 Expedition Limited 4x4. Never wrecked and passenger use only (no towing).

One of the turbo coolant lines began to leak coolant. I had the Ford Premium ESP, which covered the repair. (At the same time, the engine vacuum pump began to leak oil - also repaired). This was in the 70,000 - 80,000 mile range.

I recall the turbo coolant line was an involved repair, and the mechanic at Ford broke several exhaust manifold bolts during the repair. The ESP paid for the repair and the extra labor charge for repairing the broken bolts. The turbo had to be removed or loosened, but not replaced.

The line wasn’t leaking a lot, but I noticed small drips on the garage floor and also the engine coolant reservoir dropped about 1-2 inches in a week.

I don’t know if the coolant leak would accelerate quickly, as I took mine to the dealer and said fix it.

I’d be leery of making a 90-mile drive with the leak. Coolant leaks can worsen and where your engine is leaking is a difficult repair area. I am always cautious and do not risk a long drive with a known issue such as leaking coolant.

I wish you the best. Good luck.
 

Fastcar

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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.

View attachment 87300
 

Fastcar

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Were it me I'd run it. As 17Expi says, it is probably one of those little O rings. Keep a jug of water with you just in case and keep an eye on it. No stop leak!! I'm surprised the dealer didn't want to sell you an engine.
 
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H60John

H60John

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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.
You are right, I mean we can already tell where it’s coming from. I appreciate it!
 
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H60John

H60John

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Were it me I'd run it. As 17Expi says, it is probably one of those little O rings. Keep a jug of water with you just in case and keep an eye on it. No stop leak!! I'm surprised the dealer didn't want to sell you an engine.
100% surprised as well! I tried to call them and they said they have seen new cars go 1000 miles and need new engines so I should have bought a warranty if I wanted protection. I appreciate the input!
 
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H60John

H60John

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I bought a new 2015 Expedition Limited 4x4. Never wrecked and passenger use only (no towing).

One of the turbo coolant lines began to leak coolant. I had the Ford Premium ESP, which covered the repair. (At the same time, the engine vacuum pump began to leak oil - also repaired). This was in the 70,000 - 80,000 mile range.

I recall the turbo coolant line was an involved repair, and the mechanic at Ford broke several exhaust manifold bolts during the repair. The ESP paid for the repair and the extra labor charge for repairing the broken bolts. The turbo had to be removed or loosened, but not replaced.

The line wasn’t leaking a lot, but I noticed small drips on the garage floor and also the engine coolant reservoir dropped about 1-2 inches in a week.

I don’t know if the coolant leak would accelerate quickly, as I took mine to the dealer and said fix it.

I’d be leery of making a 90-mile drive with the leak. Coolant leaks can worsen and where your engine is leaking is a difficult repair area. I am always cautious and do not risk a long drive with a known issue such as leaking coolant.

I wish you the best. Good luck.
I appreciate the input. I am very glad you had coverage!
I may shift priority here to repairing my wheel bearing on my Ford edge while I save up for the turbo line repair.
I was hoping to drive both of them until the wheels fall off. Good thing I didn’t say until the turbos have issues
(Trying to stay positive here)
 
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H60John

H60John

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here is a better picture do you guys think internal or external?
IMG_8786.jpeg
 

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17expi

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here is a better picture do you guys think internal or external?
View attachment 87303
It's hard to say where it is coming from with a picture or even being there but it's just one of the cooling line O-ring seals and you could do it yourself., It shows you how on YouTube and the parts are cheap........not internal. Myself; I probably wouldn't fix it. Go on vacation over the mountains and don't worry about it. Just watch the coolant level once in a great while.
 
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