OK, saw this burried in another thread and was SO impressed with the results, I thought I would report it here.
Checking the throttle cable coming from the back of the accelerator, look for play within the cable where it connects to the top of the peddle. I pushed my peddle down to the floor, grabbed the cable and pulled it as far as I could until it felt firm. Then I released the peddle. I saw about 1-2" of bare cable hanging there. So I cut a section of a Bic pen (like another lister had done) and slit it down the side and placed it on the cable, then I zip tied it a few times.
Now the peddle is a lot higher, but the full power of the truck came alive. The response is better (probably because of not having to mash the peddle to the floor), but the strange thing is, my shifting problems went away! It kicks down normally and shifts where it should ANy ideas why this worked?
Well, if you haven't done this, go do it. I know it isn't a "mod" and it can be fixed by getting a new cable, but why spend more when you can do it for almost free and it only takes 5 minutes (if that).