My 1993 f150 with a 351w and e40d is stuck in 4 low. It will shift in and out of 4hi just fine. But when I shift into 4low both the 4 hi and 4low lights next to the buttons strobe fast and it won't let my shift out of 4low. I've Tryed disconnecting the battery and it still dos it. Any ideas

 

The shift motor could be getting "lost". There's an end stop that wears and then the shift computer loses track of where it is so it can't figure out where to shift to.
That's a possibility.
Or it could be in the shift computer or transfer case of course but I'd start by reading up on the shift motor and how it works.

 

Ok thanks I'll look into the shift motor