I have a 95 k2500 xclb 350 tbi 4l80e. Trans slips in passing gear and sometimes it gets stuck in second gear. Sometimes I'll run it up to 45 -50 then put it in neutral and shut it off and wait about 10-15 seconds then restart it, put it in drive and it will shift after that. My question is what year 4l80e are compatible with a 95? I have already changed the filter and fluid in it, plus the shift solenoids. Still the same thing. Help