What
Tickle and
FlyguyXX have experienced on the B777 is completely normal, it's heard on every flight.
It's the linkage of the main gear steering clunking about during taxy manoeuvres, particularly noticeable during push-bacl.
The only time that you won't hear it is when it's locked out, and the triple bogey becomes rigid, then you hear a lot of rubber screeching on the tight corners instead
Regards,
Old Smokey