ls1 auto problems

Hi wonder if you could help me. My ss 2005 im. Having an issue since 2 yrs ago spend on several places and parts. The issue is not changing gears and no speedo function. I've changed speed sensors throttle body and crank sensor. Use to reset pulling 10am fuse but it would go back to that...

Hi guys While driving along at a slow speed It feels like the auto box( vz ls1 auto) slips out of gear ,put your foot down and you feel a clunk and off it goes. Slight atm but wanto fix before it gets worse Any info would be great Needs a service ect ? Cheers