ATF or Coolant Leak? Can't tell

Long time lurker - joining team Tundra/Sequoia with a 2010 5.7 w/ 187K miles. Noticed a couple drops of red fluid on garage floor and took a look underneath. Area is near what I believe is transmission cooler - none of the lines look like they are leaking coolant - but it's hard to tell. Truck does have towing package. Recently had new radiator and all new coolant replaced. Did ATF check and level was fine.

Any ideas? Seen this before? Thanks for your input.

 

Looks like coolant to me. I’d look near the water pump.

 

That's definitely coolant. I would clean it all up, then check for the culprit. Good luck.

 

Thanks for quick reply- I dropped the skid plate and was dry as a bone - if water pump leaked would it drop into it? I thought the water pump was further toward the front of the truck.

Re: transmission cooler - meant the thermostat (where I put the pin in to check ATF level)

 

Water pump is original to the truck. I do know that.

 

Not water pump. Water pump is on the front of the engine. That picture is the bell housing above the starter.
My guess is that you have a pinhole in one of the lines.

 

Find the highest point of pink and go from there. It is definitely coolant. ATF wouldn't leave light pink/white traces when it dries.

 

I would look into your heat exchanger as it goes in the cab behind the dash. Check tjebpassenger side carpet if it's not wet, then inspect the hoses that go toward the heat exchanger or feed towards the back of the engine.

Water pump will drench your engine block behind the oil filter.

 

valley plate coolant leak probably

https://www.tundras.com/threads/coolant-leak-but-where-is-it-coming-from.104026/

looks similar

 

Thanks all for replies. It definitely aligns with what others have described as the valley coolant leak.