I’d be curious to find out if anyone else has this happening also, my wife says her TB makes a bunch of clickety click noises a few minutes after shutting off.
I sat in it yesterday for 10 minutes after shut down and didn’t hear anything
I verified the clicking noise today while sitting in the pass seat after shut down, definitely sounds like relays as @Remanaz stated.. sounded to me like it was fwd of the firewall over on the drivers side possibly in the area of the ABS system.
Found this statement from a user on a GM forum:
“It is the new electronic braking system doing a system check. It does this after the truck has been shut off. I worked on it while it was in development”