FIPG sealant failure - coolant leak at heat exchanger

In March '21, I bought my 2021 Double Cab, mostly as I wanted the supposedly rock solid 5.7L V8. I was well aware of the cam tower sealant leak issue and was assured by the sales dude that it was no longer an issue. Not that I completely bought the explanation, but it wasn't a deal breaker for me. Prices were starting to climb and inventories were dropping. Anyway, a few days before I brought the truck in for the 5k checkup, I popped the hood and noted that the coolant level in the reservoir was low. Didn't cross my mind that there might be a bigger issue - just thought somebody screwed up at the factory. At the 5k checkup, they put the truck on the lift just to take a look underneath and sure enough there was a bigger issue. Visually, there was quite a bit of coolant splattered all the way down to the transfer case. As was later determined when the engine was dismantled, there was a coolant leak near the heat exchanger buried deep in the engine block due to a FIPG sealant failure. I'm guessing some of you will have schematics and can better describe the issue. Feel free to chime in. Regardless, this was a major manufacturing defect out of the factory - not what one expects when buying a Toyota. My 2005 Tundra has had no major issues in 280k miles. I wasn't expecting to deal with any issue of this magnitude with the '21 Tundra for a long, long time - if ever.

Since I bought my truck in March 2021, I'm guessing the engine was manufactured in February 2021 and possibly earlier. I also later heard the dealer that fixed my Tundra had another Tundra in the August timeframe that had a similar FIPG sealant issue. Based on these two data points, it would appear that Toyota had a manufacturing process issue between February through July at a minimum.

Yes, the issue was fixed under warranty but still leaves some level of doubt in the overall build quality. I am interested to hear of other similar experiences and also the technical assessment of the folks here.

 

A couple of 21s have had this issue.

 

Do you think this issue has the potential to be a slow reveal on x number of other 21's - similar to the cam tower leak? I suppose I'm glad my issue was identified early without any damage from overheating or other. But want to make sure other '21 owners are aware of this potential issue in case they suffer a sealant failure later on.

 

This seems to be an issue right off the lot on drive home or within first few hundred miles

 

How are people identifying the leak on the drive home or within the first few hundred miles? For my issue, there would have been nothing to indicate I had a leak until probably 3k miles. At that point, the only indication would have been low coolant level in the reservoir. Particularly with a new Tundra, I don't pop the hood often enough to quickly catch a low level in the coolant reservoir. Perhaps others would. There was no coolant leaking on the ground. Just curious how this is being identified by others.

I hope you're right and this issue is caught within the warranty period for effected owners. But I won't be surprised if this drags out similar to the cam tower leak issue.

 

Regarding the use of sealants in engines, such as RTV and FIPG, is this a Toyota thing or do other manufacturers use sealants in a similar manner? Or do other manufacturers use gaskets?

 

I wonder if the sealant failed or it leaked because of poor application to the surfaces involved?

One can be corrected the other cannot.

 

Yes, I would be curious on the root cause of the issue as well. The tech that worked on my Tundra thought the sealant failure was due to surface contamination when the sealant was applied in the factory. But that was just his guess. Guessing some Toyota engineers are trying to figure out root cause and potential number of engines impacted. Not that any such information will be released to us. I just hope all failures are fixed under warranty.

You're right though, I'm guessing/hoping the sealant didn't fail - as my thread title states. It's probably a seal failure that technically can be corrected. But from my data points, there's at least 6 months of production at risk.

 

I'm having the same coolant leak on my 98000 miles, 1794 edition toyota tundra 2014. It seems like the heat exchanger sealant failure is a common problem for the 3rd generation tundras.

 

Please enlighten me on “heat exchanger.” Know what they are on the machines I work on but didn’t know vehicles had them.

 

That's a 2.5 Gen, FYI.

 

I'd also like to know. I've never heard of a heat exchanger inside of an engine. The only thing I know off that would be considered a heat exchanger is the radiator.
I believe there's also a heat exchanger that helps get the tranny fluid up to operating temp from a cold start with engine coolant. Is this related to that?

 

There is no heat exchanger buried deep in the engine that I have seen and I have looked at a complete teardown of a 5.7. There is an oil cooler by the filter housing. If there was coolant leak in the mysterious HX buried deep in the engine, that engine wouldn't be running. And how does a leak deep in the engine leak to the outside. I would be more worried about the mechanic working on my truck than the engine assembled by Toyota.

 

Would you be able to get a pic or 2 of the area where the leak is coming from and post it? This has me curious.

 

Found another thread. It's not "inside" the engine. It's the little heat exchanger on the side of the trans that transfers heat between the trans oil and engine coolant.
https://www.tundras.com/threads/2021-coolant-leak.83002/#post-2100564
This subject is new to me. Just wanted to clarify what we were talking about so I can keep an eye on mine.

 

My initial comments were based on a relatively brief discussion with the Toyota tech who did the warranty work. And on top of that I'm no engine tear down expert or even a rookie. What I do know is that a lot of parts had been removed from the engine to expose a component in the engine that allowed the antifreeze to (as I understood it) circulate and assist in regulating engine temperature. I don't know all the specifics of the leak but the FIPG seal in whatever it might be called other than heat exchanger failed, which allow antifreeze to leak out onto the transfer case area. Frankly, I was so pissed off on having a major defect issue at 5k miles, I probably didn't hear all of the explanations or information provided. But I was hoping to provide enough information for someone who could fill in the blanks. Not looking like that's the case.

 

It worked for me. It piqued my curiosity and caused me to look into it. I don't know what it's official name is, but the part that you had a problem with is in fact a heat exchanger. I didn't even know this part existed and I'm on my 3rd Tundra. So I'm glad I saw this thread. I just wanted to clarify a few of the finer details for my own education, so I would know what to look for on my own truck.
Also, for posterity.

 

Does anyone know if other manufacturers use sealant in a similar manner? I find it a bit odd that a critical seal is created by hand with a tube of sealant instead of using a gasket. Seems prone to human error....hope the person wasn't hung over when the sealant was applied, etc. Between the seal for the cam towers and call it the heat exchanger for now, it appears that the two points have an elevated risk of sealant failure. And both are a very expensive to fix if not under warranty. I haven't heard of similar use of sealant by other manufacturers.

 

It wasn't anything against you. I was just saying it to answer the other members questions. It was more geared toward the tech. Sometimes their answers leave people up in the air. I would also be pissed AF. Nobody wants a brand new vehicle with issue from the get go. I actually had a similar experience with a 6k Acura ILX, leaking oil, rear main seal, common issue. The dealer that sold it to me overfilled with oil by 1 quart. They were in BFE so I took it to a closer dealer. They proceeded to tell me that if I did an oil change with them then they would warranty the oil leak. Told them to fuck off and took it back to the selling dealer. Covered under warranty, no questions asked.

 

See the below thread from my experience on the coolant leak I had. Maybe this will help.

https://www.tundras.com/threads/what-the-heck-is-this.105443/

 

Ford in their mod motors where the 2 timing covers meet the block and gen 1 sb gms where the heads, intake and block meet.