GPS and Bluetooth

When I connect my GS3 to my truck through bluetooth I found I loose the ability to hear my GPS directions. is there a way to make the GPS directions either come through the speakers in the truck or the phone speaker when its connected to bluetooth.

Thanks

 

Searching on bluetooth because I have an issue. But I know the answer to this one... if you want to hear the GPS directions through the head unit then you need to have the media setting of the HU on "bluetooth audio" which means that you can't be listening to music from another source. It would be nice if you could. So drive in silence for a hundred miles just to hear "in 1000 feet, take a right...."