I have a 2006 f150 with the 4.2 v6 and the tranny went out . I replaced it with one out of a 2008 f150 with a 4.6 was told it would work by several mechanics ......it goes in gear fine, pulls fine , but won't shift ..... overdrive is flashing "od off " (I have the button on the shifter ) and I'm getting a transmission fault on odometer did I forget something or do I need to reboot the PCM? I am a landscaper and my truck is how I make my living and I have to work tomorrow ..... Please help

 

You need to read out the OBD2 codes with a scanner that can read Ford transmission codes.

How did you get a 4.6 transmission to fit? The 4.2 and 4.6 have different bellhousing bolt patterns.