Have no idea what these tubes are!

[ceejay]

To elaborate ( might not be needed)
The hoses connected to the green valve with the nails suck in em. Pull the nails out, remove the hoses. They create NO vacuum so there’s no need for caps/ hoses.
Also some of your hoses look well past expiration date. Soft collapsing hoses or weather checked hoses create undue problems. Replace them.

Yeah I know, they're on my list. Truck was basically a roller when I got it earlier this year.

 

[ceejay]

Thanks for the help everybody! I probably have some more random stuff I'll post in the future and ask what it is haha.