I have a 2000 F150 aport 4x4 c/w 5.4L, auto. and electronic shift control.
It will not engage in high or low range.
When selecting either range, I hear it select electronically and it sounds like it mechically engages but 4WD doesn't pull in.
Any suggestions?

 

Do the 4wd lights come on? If they do and the t-case engages it will more than likely be the shift fork in the front diff. for some reason Ford made them of plastic and the new ones are aluminum if I do recall correctly. I had the same problem with my 03, it would sometimes engage and then slip out. Oh and Ford tells you that you will have to drop the whole diff. not the case just the passenger side CV axle and axle tube. Its hard but it will happen.