What hose is this?

[kstemple9]

 

[whtbronco]

There's 2 vacuum lines there. If you follow both of them to the left in the picture they connect to the 4wd hub solenoid. At the solenoid the lower hose connects to the engine and the upper connects to the 4wd hubs called Integrated Wheel Ends at the front wheel bearing hubs.

The vacuum line to the engine also splits off and gores through the firewall for the HVAC system.

 

[kstemple9]

I need to replace it.

There's 2 vacuum lines there. If you follow both of them to the left in the picture they connect to the 4wd hub solenoid. At the solenoid the lower hose connects to the engine and the upper connects to the 4wd hubs called Integrated Wheel Ends at the front wheel bearing hubs.

The vacuum line to the engine also splits off and gores through the firewall for the HVAC system.

Thank you!

 

[whtbronco]

This will replace most of the vacuum assembly:

https://www.amazon.com/Ford-4L3Z-3A788-AA-TUBE-ASY/dp/B000NTJMTI/ref=sr_1_10?crid=24EM3EUBEC822&dib=eyJ2IjoiMSJ9.Kya5G_M0r7TElzDyPW9ONla3hAA3MGGDmN4DgdvqqvQWx4LtJ25T6tiMnoVsYHvWd8I3V3Rrq0PWjBW8olh0P7hL4dQ23aHHI1bDSM78kLl6YwpST0UGgcmdJiLN4qNqyHucPt7kZpBvKtkeuosLK_2_JuO-MpVzObVv_WcB4MnslCiCnO6eQ8czAiG6PzXqo5V2i9__3E9jEkidpm1LBZbYS_LqZrXZfI-8_F2Heqk.k8dNwS0bDJnioxd6t6Vztr-sfChE_Fbal5DC4SbQe0I&dib_tag=se&keywords=FL3Z-3A788-A&qid=1731113195&sprefix=fl3z-3a788-a%2Caps%2C168&sr=8-10

I used that plus an 8-10" section of 1/4" hose and 1 additional check valve:

https://www.amazon.com/gp/product/B000C5HZ24/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

That's what it took to replace the entire assembly on my 2004.