The plastic bushing at the end of the column where it comes threw the firewall. A very know problem on the JK. Mine has been doing it so long I only notice it on the days it doesn't make noise....
Was out driving around Friday night when the Wife and I spotted this out by the Tims on Stony Plain rd in West Edmonton.
I don't know who owns it but I have rig envy....
This thing is really cool and if I won the lottery I would have one myself.