I have a 2001 F150 5.4L 4WD. The transmission is out. I'm told, based on the VIN, it needs a 1L3P transmission. I bought a 3L3P transmission and was told it was interchangeable but the salvage yard says I can only use 1L3P. Does anyone know if these 2 are interchangeable? Thank you!

 

Exactly what is the 3L3P transmission out of? If it's 2004 or newer, not compatible.