Well sort of, yes you can have GPS in your AVHP4000DVD unit or any AVH series that has RCA input (red, white, yellow plugs).

 

First I used Nokia 5800 XM and then wife's N8. Both work great. Used garmin mobile xt but didnt like it. Then bought Sygic for $30 CAD and it was so much better. You can hear the gps instructions and routing from car speakers and you can still play music/radio and have the GPS run in your background (no sound for gps then). I liked this unit till I sold it and got avic-x920bt.

 

The bad sides are no on screen input, wires are kinda dangling which makes it look sort of cluttered. Otherwise, it was awesome.

 

Thank you, AVIC411!