i have a 2002 150 4x4 5.4 is my transmission the 4r70w or the 4r100? apparently the seals between my tranny and transfer case went bad and all the fluid drained into my transfer case leave my tranny with no fluid which burnt reverse out...the mechanic told me its very common on my style 150 for this to happen...whats the easiest route to fix this? how costly is it?

 

What is the trans code on the door sticker? "E" is 4R100, "U" is 4R70W.