Headed up I-35 out of OKC today when I casually look at the back up monitor and see the Hummer in echelon formation with the coach. I slow down oh so gradually and ease off on the shoulder.

Upon inspection, the pin that holds the tow bar adapter to the Hummer had come out and the safety cable was holding that side of the truck in line (sort of).

It looks like the safety clip that secures the pin came off and allowed the pin to work out. Then the adapter slid out of the square tubing attachment.

Luckily, the tow bar is set up to swivel when the adapter came loose. And equally lucky was the fact that I had an extra receiver hitch pin and it was a direct replacement for the one that came loose.

I can't imagine how the retainer pin came loose, but I can tell you I will pay more attention to these in the future.