What are these frame plugs for?

Hi guys, i want to know what these plugs are meant for. They are in the area designated in the manual for jacking points. Also if anybody can check their truck and feel the frame rail between the plastic things and the tranny mount cross member and check if the surface is perfectly flat or slightly concave feeling going up please. Thanks for reading.

 

Bump

 

Whistling sounds... seriously.

 

Yes and there should also be plastic plugs in your lower control arms with a 2017

 

just look at my undercarriage...that's what she said...lol

 

Russian listening device

 

What are they listening for? The howling or the whistling?

 

A little of both

 

I read these plugs allow water to drain out of the frame while preventing water from getting in (through the same hole)

Here is the thread and post with the part number-


https://www.tacomaworld.com/threads/part-number-needed-frame-plug-cap.517334/#post-16352407

 

thank you sir!

 

Those gray plastic pieces attached to the frame.