I have searched here and seen that the small magnetic pad that goes under the GPS is needed to get a proper ground plane. Is this only if it is mounted on plastic or some other non-metalic surface. I have mine on the roof of my truck and my GPS is working great so far. I was just wondering if I need to go back and put that pad under there.

No. That's just for use if you're not on a metal surface. You're fine.

I thought so, but just wanted to make sure.

Thanks

you dont need it regardless. i have never used that pad on the dash, and ive never had problems because of it

you dont need it regardless. i have never used that pad on the dash, and ive never had problems because of it

It made a HUGE difference for me. Perhaps there's more metal under your dash than there is under mine?

Depends a lot on the placement of the antenna and the vehicle's dash structure. I've done some where reception was perfect without the pad and others where the reception sucked. Though I do tend to use it if for nothing more than a way to stick the antenna to the dash without having to go find double sided tape.