Hey everyone recently bought a new F-150 and wanted to make sure I know what transmission I have so I know whether to put Mercon or Mercon V in. I have done research and have found conflicting details. Some say it is a 4R100 and others say it is a 4R70W. My truck is a 2000 F-150 Supercab 5.4 L V8 2WD.
Thank you!!

 

Doesn't matter - Mercon has been replaced by Mercon V. Use Mercon V in either one now.

The sticker on the door jamb will tell you which trans you have - trans code E is 4R100 and trans code U is 4R70W.

I suggest you drop the pan and drain the torque converter to do a complete fluid change.

 

I have code U. Thank you!!

 

For your truck, the 100 only came in the 7700/F250LD trucks anyways...and the L.