need help please

[spideymason]

I have a 03 silverado 5.3 4wd z71 and I recently replaced tranny out of a 99 silverado 5.3 4wd z71 and its coming up with alto of random check engine lights and in rep does anybody know if the tranny is the problem my original trans was a 3kcd replacement is a 9kcd all plugs were the same bolted up goes in gear but having rep problems

[Supreme Pizza]

Try resetting the computer by clear the codes or disconnecting the battery over night. Check to make SURE all the ground straps from the wiring harness are in place, and didn't get missed on the installation.

[spideymason]

I got it outta rep was a ground but now its not shifting and torque converter code popping up