I will be replacing the factory HU in my 2011 FX2 with an aftermarket unit soon, probably Alpine.

I am NOT interested in satellite radio but a lot of aftermarket HU's do make use of GPS and I wanted to see if the antenna that is on the roof of my truck (passengers side) is a GPS antenna or strictly SIRIUS/satellite. If it is a GPS then good; I can make use of it.

 

I wouldn't think so since they are tuned for different frequencies.

 

It's satellite only.