Radiator leak / coolant disappearing

[DavidC]

You're preaching to the choir. I'm an engineer at Viasat and we're dealing with this right now:

Viasat’s new broadband satellite could be a total loss

The mission now in peril is thought to be valued at roughly $700 million.

arstechnica.com

Although we outsourced the failing part.

 

[JasonH]

I had a coolant leak. Turned out to be the water pump, but that was over 140,000 miles and a Gen 1 Ecoboost. I suggest adding some dye to the coolant. That in combination with an IR light will help you determine where the coolant may be escaping the plumbing.

 

[coyote-dogfish]

Well, there are other girls in town. I bought mine, since at the time, it was the most technologically advanced full-sized SUV available. None of the other automakers had refreshed or redesigned their large SUVs. Though I said, I'd buy another one, and I would, I would start my research over again since Chevy has since re-designed the Tahoe/Suburban/Yukon and by now one of those, or some other SUV, may be better than today's Exp.

Same exact way I ended up with my '18 Exp! But yeah at this point I'd take some less tech and downsizing just a tad in favor of more reliability. I would even pay more $$ on the front end to save the constant worry and hassle. My wife is always afraid it's going to leave her and the family stranded. It's also very "flaky" in other ways I didn't mention (don't wanna hijack this thread even further!). Not sure how that large SUV comparison would look now in 2023, as you said - if you do it please let me know! haha In almost 2 years I literally have never had more than about 3 or 4 months of running this car without problems and trips to the dealer, etc. And, as I was saying, my Gen 3 had less issues, but def still had them. And my Flex was no picnic either.

 

[coyote-dogfish]

Unfortunately, this is what happens when companies try to manufacture very complex things as cheaply as possible on a global scale. Just look at the Boeing 787 debacle.

YUP! Same story with the large company that I worked for that did things cheaply on a global scale (different Industry entirely). Well... cheaply on the front-end!

 

[coyote-dogfish]

I had a coolant leak. Turned out to be the water pump, but that was over 140,000 miles and a Gen 1 Ecoboost. I suggest adding some dye to the coolant. That in combination with an IR light will help you determine where the coolant may be escaping the plumbing.

Good advice, I can try to do this. I have to use my buddies garage/lift though, and I just need time to work on it!

 

[coyote-dogfish]

As I said... my wife and I both WANT to love this car. It felt initially SO much better than our Gen3 Exp. From the interior roominess, the improved infotainment system, to the drivetrain and improved fuel economy - to Sport mode, which makes the car feel like something way sportier than it should given it's massive size/weight - lots of incremental improvements. But man oh man, I'm losing faith quickly that it will ever be even moderately reliable! At least I'm speaking for mine - YMMV, but, I will also say almost any problem(s) I've had - no matter how obscure or weird (mirrors whacking out and going crazy in and out ... that one is so bad it is laughable) I will immediately find others here with the same issue(s), which makes me think it ain't just mine!

 

[coyote-dogfish]

I think I've located my problem and I just wanted to give an update in case it helps anyone else troubleshoot a similar problem. First, my initial indication something was wrong was the fan speed (I believe as the OP stated here). I noticed the fan kick up to a much higher speed (and much louder sound...most have been running hotter, but it's been super hot outside so I thought it was just due to that). Everything seemed fine until one day it almost overheated - red warnings on the instrument panel that the temp was high ~250-260 ish. We got it home and let it cool - and noticed it was low on coolant and added some - then I ran it idling and could find no leak. I then drove it gently and then noticed it was down again some - so I added more fluid. This cycle continued with no obvious leak, and adding coolant. So - last night I got it up on a lift and ran the vehicle and same thing - couldn't see any leak anywhere. I then increased engine speed to around 3500RPMs steady - and after about 30 sec - boom, it was dripping down the front cover from what appears to be the water pump. So, presumably it's a bad water pump and/or seal. I'm going to replace the water pump (and thermostat while I'm in there and it's all ripped apart) this weekend. What a PIA - again this car has 52k miles. At least I know what's happening?!

 

[JasonH]

I then increased engine speed to around 3500RPMs steady - and after about 30 sec - boom, it was dripping down the front cover from what appears to be the water pump. So, presumably it's a bad water pump and/or seal. I'm going to replace the water pump (and thermostat while I'm in there and it's all ripped apart) this weekend. What a PIA - again this car has 52k miles.

Glad to hear you got the problem diagnosed. Very disappointing that the water pump failed so soon. If the Gen 2 is anything like the Gen 1, it's not a difficult job, just tedious. Make sure you have a selection of extensions and universal joints. An electric ratchet is helpful to expedite bolt removal. I had to pull all the charge air plumbing to get access. That was the hardest part because the engine bay is cluttered and reaching down to the turbo was a pain. It's also messy if you don't vacuum out the fluid. I didn't bother draining the radiator because my coolant only has 30,000 miles on it. I just pumped out what I could from the well behind the thermostat housing and turned the coolant hoses upwards. There are tutorials on Youtube.

 

[coyote-dogfish]

Glad to hear you got the problem diagnosed. Very disappointing that the water pump failed so soon. If the Gen 2 is anything like the Gen 1, it's not a difficult job, just tedious. Make sure you have a selection of extensions and universal joints. An electric ratchet is helpful to expedite bolt removal. I had to pull all the charge air plumbing to get access. That was the hardest part because the engine bay is cluttered and reaching down to the turbo was a pain. It's also messy if you don't vacuum out the fluid. I didn't bother draining the radiator because my coolant only has 30,000 miles on it. I just pumped out what I could from the well behind the thermostat housing and turned the coolant hoses upwards. There are tutorials on Youtube.

Yeah it is disappointing... again. Unfortunately I should have just purchased the extended warranty, but then who knows the game becomes trying to get things covered etc. And the warranty isn't cheap, even with the high deductible. Thanks for the tips I've seen some youtube videos. I guess the 2018 has no "coolant crosspipe" going through the block to the pump like I've seen on some videos?

After this I have to figure out what to do about a leaking rear evaporator! Ughhh

 

[coyote-dogfish]

Speaking of the coolant crossover pipe I've seen in the video I was watching (it's for an F150 and some expeditions I believe). Does the 4th gen not have a crossover pipe from the pump to the back of the block? I can't find it or the o rings, so I'm assuming not? Can anyone verify?