What the heck is this???

I had something similar and it turned out to be a leak coming from the coolant valley gasket. fixed under warranty.

 

I believe mine is in the same area. The coolant valley under the intake manifold. The plate on top of the valley is held together with silicone. Service advisor said everything will be covered under warranty and approved a loaner car for me.

 

Awesome.
Glad your truck is ok. Glad dealer took care of it

 

I went to pick up my loaner vehicle (4Runner) and get my kids booster seat out of the Tundra. I talked to the technician and he said it doesn’t look good at all. They re-siliconed the coolant valley twice and it is still not holding pressure. He said he had already ordered another engine block to be safe. On a more funny note, when I went to get to get my kids booster seat I noticed the front tires were deflated but not all the way flat and there was coolant everywhere. So I asked the technician what was going on. He said it makes it easier to work on the truck with the lift. He also said, that it was hard to see such a nice truck going through this. I feel confident the truck will turn out fine. Thank you again everyone!!!

 

Just a quick update. The dealership was able to reseal the coolant valley on the third attempt and replaced the heat exchanger under warranty. I have had the truck back for a few weeks and no more leaking and/or “bleeding”. Thank you again for everyone’s help and now I see other members may be having the same issue.

 

Looks like I’m having same issue with a 2021. Did you have any issues with warranty ?

 

No issues with the warranty what so ever with my dealership or Toyota @Garbear41 . My bill was $0 and they were even nice enough to provide a loaner car. The dealership had the Tundra for about a week. No issues since (approximately 20,000 later).