1999 XK8 Transmission
 

Ever since my battery was removed and replaced my transmission has acted up. It will bang into drive on occassion, is there any connection to the battery change out that could cause this. Does it need to be programmed?

The most obvious is that an upset engine will upset the trans. So, investigate the engine. Check for codes, check OBD monitors, check sensor data and fuel trims.

There is a connection in that the tcm and ecm will need to reset for a short time after a hard reset or battery replacement. But that should only be for a few restarts.

Banging into drive is often an indication of A drum failure, but not reprogramming requirement.

If its the first drive after a reset, the fuel trims need to relearn what is going on.
There is a drive cycle to do, to do this. I think its in the stickies somewhere.
Someone here may be able to link to it.

I did a battery reset without knowing what the procedure was.
A few short town trips etc. and things still didn't feel right.
Once I did the long highway cruise everything settled down and fuel economy and shifting improved.
You may have to give it a little time to reset and learn again.