Can hear fuel purge back into tank with engine idling. Sounds like a high pressure gurgling sound. Truck seems to run fine but recently replaced fuel tank and never heard this before. 2001 f150 super crew

 

May have something up with the fuel pump module(the sending unit and pump assy)
the return should go as low as the sock,also has a rubber nipple on the end. System puts return fuel back submerged ,so it shouldn't be noisey.
Was this tank exactly the same?
Did You Use your existing pump?
Does the fuel gauge read accurately?
Reason I ask is maybe its closer to the bottom of the tank causing cavitation.
Return noise shouldn't cause any drivability issues.
As long as you have no visual fuel leaks you should be fine.

I would still check Fuel pressure while idling just to verify its ok.

Now.... I installed a walbro 255 and aeromotive rail w/adj regulator on mine.
It sounds like a fish tank .LOL

 

That can be a cracked tube on the fuel pump as well. Should be pics online of it.

 

True