I just installed a Airforce 1 intake and a Superchips 1714 in my 04 5.4l FX4 EC. When I really hammer it from a stop it pulls hard in first and when it shifts into second I hear this loud chirp like a bird noise. It sounds like it is coming from inside the cab. I have no idea what it could be. The shift is smooth and tight and there is no slippage. Any ideas would be great..

Thanks in advance..

 

It is your serpentine belt. When it downshifts, the RPM of the engine goes way down, however the accessories are still going full RPM. The squeal a little when they slow down.
Get a Goodyear Gatorback replacement. It should stop with that belt.

 

Ditto X2 Agree

 

Thanks guys...is it okay to drive for now or should it be addressed? Also, can I change it out or does the dealer need to do it?

 

It's fine to drive. On my old 01, it did it from 20k on. I traded it at 70k with the same serpentine belt. Just annoying.

 

Thanks Kingfish for the help..Im gonna order the belt from Troyer and put it on when I get a chance..