tail gate malfunction

my 94 s-10 tail gates is weird. my friend had the truck for a few years sittin outside and 2 years ago had the tranny replaced and then gave it to me a few weeks ago, but for some reason when im drivin the tail gate just drops...when u put it up the handles hangs loose like when u lift it to open tail gate, but if u push it in and tug on the gate it holds and doesnt come down unless u lift the handle again, so why when im driving does it just come down?

stupid i know but i am new to engines and im teaching myself as i go using haynes and chilton manuals as well as posts like these and the tools i buy as problems develop lol...plz lemme know what u think

The problem is the linkage.GM has a small plastic washer on the pivot point where each linkage connects to each latch.When this linkage rusts,it then binds up under the plastic washer.Now here is a really easy fix and don't be afraid.Get yourself a propane torch,lift up the handle,find the plastic washer,now melt it.Just watch what your burning and don't burn the paint off your gate.I did this on my 98 and other S-10s,it works great!