'07 Nbs Silverado Gps Antenna

[pr73]

I am looking for the wire from the rooftop antenna to connect to an aftermarket GPS receiver. I do not have stock GPS or XM, but I do have the Shark Fin on the roof and of course On-Star. Any help would be great.

[Silverado4x4]

So you want to use the antenna (shark fin) on the roof to connect a aftermarket GPS? You cant cause that is the antenna for the onstar. Just a little info some people think if you bust the antenna off the roof that onstar will not work "say someone steals your truck and onstar cant track it cause they broke the antenna off" well onstar still works even without the antenna on the roof this is info from onstar.