does a vac line go here?

[pcoppock]

do these to connect? go 2 diff places? or stay the way they are? its a 2000

 

[badattitude]

I think that is your rear heater line. It takes hot "water" back to the rear heater core. A lot of people (me included) have removed those lines becasue they rust and leak coolant under the truck. You can follow thos back under the truck frame to the inlet of the rear heater. If your truck has been running fine, the rears line have been blocked off at the engine. You can probally remove those old lines from the truck alltogether. I said probally, be sure to make sure.