On the inside of the door connected to the handle are 2 cables. One goes to the glass latch and one goes to the door latch. The ends of the cables have a plastic casing that sits in a metal bracket on the latch. The plastic deteriorates and brakes away from the cable causing the cable assembly to slide instead of actually pulling the latch. You can buy just the cable and its a relatively easy fix. I had to do this on a '97 and my '98. If you get in the back of the truck you will be able to pull the door trim panel off after you remove the inside pull handle screw. Once you get the trim panel off you can see the latch mechanism and pop it open with a screw driver, its easier to work on open. The part number for the cable (at least for the '97-'98) is F2UZ-15264A65-B. I would recommend doing both cables while your in there, if they are not both broken the other one is not far behind. If you do both you will need to order 2 of the part number above.