So my 1996 k1500 wont grab anything in 4th gear. its like neutral. its been this way for a little over a month, but it didn't just lose it out of nowhere. When I first noticed a problem I was towing a trailer, and when it locked up I gave it some gas to get over a hill and the rpms started to flare, so I dropped it down to 3rd and it was fine. a couple days later I noticed if I put it to about half throttle, the rpms would flare while the converter was locked. a couple days after that, 4th gears was uselss. now Its starting to flare when the converter locks in 3rd. I'm assuming in a couple days that will be useless as well. Its never made any funny noises, 1st and second still work perfect although the shifts are getting sloppier. I had my mechanic check into it and he couldn't give me a straight answer as to what it was without pulling the transmission out and charging me an assload so now I'm stuck. the transmission is a monster rebuild with less than 15000 miles on it, and it got a new converter when I put that in. I'm mainly just looking for other possibilities as to what the problem could be. I spent serious money on this transmission and I don't want to scrap it over a bad converter. I'm not saying its had an easy life, but whatever it is should've lasted longer than it did.