okay so i have a 1993 silverado k1500 so my tranny when out will the 3-4 clutch pack burn up i had another tranny so i had my tranny guy just switch them out he said and i saw them the clutch packs we were putting in were good and i agree it worked fine for about a month, now i will be cruising at about 50-70mph and i try to pass somebody and when it kicks down it just revs up and slips, now if you just give it alittle throttle it will do its little kick down and do fine, the tranny shifts flawlessy i have had no problem with it at all and also i have a really bad vibration at about 55-65mph i have read and been told that it is my torque converter i have done the slighty hold on the brake and let the torque converter do its thing, and the vibration gets alittle better but not much i have two other torque converters cause i have put a couple of trannys in this truck cause i like to crack tranny's in half. i want to know if its the torque converter, or the silonoid, or something any info is well thanked i am very automotive mechanical just didnt take the transmission classes.