For those that own the DNX5140 or DNX5160 Kenwood car nav system, I have confirmed that though it is not listed, the GTM11 traffic receiver will work. The GTM11 is an older unit that can be found cheap. It plugs into the mini usb port on back of the Kenwood. I would imagine that it will work with all Kenwood navigation systems.

I purchased a mini usb extension cable (male x female) and ran it into the glove box. I plugged the GTM11 into the extension cable. When I want to do map updates, upload routes or poi's, I unhook the GTM11 and connect my laptop via the extension cable.