just installed a whole new system. I dont know how or what to do to allow me to keep my XM. I have a JVC head unit if that helps........

 

you need an XM receiver and have to get XM to transfer the serial to the receiver iirc.

 

great.... do i need an antena too or no, how do i access my current antena....

 

to use your current one(as in the regular antena for your fm/am stations) i think you need an xm/fm/am modulator, i think i have one somewhere

 

my shark fin antena, is that my onstar or XM

 

I'm not that familiar with the NNBS trucks, but I think the shark fin is for Onstar and the rounded one is your XM. You can use the existing XM antenna but will need to modify the connection to the new XM receiver. In the NBS trucks, the factory XM receiver is behind the glove box. You will need a new XM receiver that is compatible with the JVC head unit.