I have a Nuvi 40 with lifetime updates. I also have an older Nuvi 765T that doesn't have lifetime updates.
Is there any way I can take the maps from my Nuvi 40 and use them on my 765T? I'm thinking this may be easier than trying to download and install maps from here, but frankly I just got these Garmins and I'm a total newb to how they work.
As best I can gather from the Garmin forums, I can unlock the Nuvi 40 maps, but I don't know where to go after that.
For example:
1) Do I unlock every .img file, or just some?
2) The paths are different on the two Nuvis: does that matter?
3) Do I have to use Mapsource to put the maps onto the 765 after I unlock them, or can I just transfer them in Windows?

If there's a thread or sticky I'm missing that explains this, pls point me there. I've been floundering around here for over an hour.
Thanks

The maps will work but they may not be a complete release of North America. The only IMG you need from the 40 is the gmapprom.img which is the map. That is what you need to unlock.

If you have JCV files in the 40 they are not compatable for 765. You will need to get the correct 765 JCV file here.

If you care about using 3d building views for the 765 tou will need to get the file here and unlock it if it's not already unlocked. The filename is gmap3d.img

The JCV an 3D files must match the same version map as what tou take from the 40 or they will not work. They are a matched set with each release.

Thanks for your knowledgeable response. Given what you have said, it looks like I was overly optimistic in thinking this would be easy.
If I just download the North America maps from Navitotal will I have to worry about the matching of the JCV and 3D files?
If I do that (download the maps from Navitotal), do I have to install them with mapsource or can I just plug them into the 765 using Windows?

You can download unlocked image file and 3d.img and also jcv file from here and just copa them into the right folders of your nuvi.

But note, if you need Europe maps, your nuvi 40 uses 'unicode' version, but your nuvi 765 uses standard NT version.

I feel like a dunce, but when you say "You can download unlocked image file and 3d.img and also jcv file from here," where is "here?" I managed to download the North America map image, but that only gave me a file gmapsupp.img. I can't find where to download the 3d and jcv files. And when I search for "3d" on the Garmin forum I don't find anything, either. I'm pretty much flailing in the dark here.

That's an easy one. The 3D for the 2014.1 versions of the maps have not yet been released by Garmin. Until then, those files are not available.

They are available if you look at the 2013.4 version of the map.