I have the Newmar equipped Rand McNally in-dash GPS in my coach. I was unable to find any way to interface to it with my computer to do an update (With the RM Dock). There was no SD card, no interface port, only a DVD slot, that I thought was more for music and the like. So, yesterday, Saturday I e-mailed Rand McNally asking them how I could do it. To my surprise, and delight, I heard back via e-mail mid day, on Sunday! Great service!
Anyway, they told me there was definitely an SD card somewhere in the area. Armed with this new positive information, I once again approached the unit, this time with flashlight in hand.
Well HELLO! There it was! Not easily located. The SD card was located on the very back edge of the bottom of the screen. It had to be powered open, and then it could just be seen. I had look in this area before but with poor lighting, and even though I ran my hand over it, I missed it. Anyway, plugged in my computer and wow, 32 meg of updated streamed in within a few minutes.
Now I will keep it up to date. After all, with Rand, all the updates are supplied free for life!