bought a transmission on the web and when i got it the neutral safety switch was broken so i bought a new one any ways i installed the transmission on the truck and not knowing this the neutral safety switch i took off the assurance bracket first and installed it in the park postion filled the tranny and started up the 2001 SILVERADO 4.3 TWD truck . let it warm up nd then i tryed to select the shifter to the gears the tranny was slipping all the gears P D R123 after all that i looked up the web and found out that i installed the neutral safety switch wrong thinking that it was the problem now the selecter switch is lined up with all the gears and the tanny still slips threw all P D R 1 2 3 WHAT ELSE COULD IT BE I LEFT THE TRUCKS REAR END AND PUT THE IN R D N 1 2 3 POSTION GIVES IT GAS AND THE TRANNY WORKS WITH HIGH RPMS ON THE GROUND IT DOSENT MOVE IDONT KNOW MAYBE I BOUGHT A MESSED UP TRANNY I CHANGED THE TRANNY FLUID AND FILTER NOTHING