Well, after seeing the gen 5 again, i am curious, can it be done ? The firmware in the nav system must be upgradeable at Lexus ?? i wonder if the nav brian is actually different in terms of hardware....The screens are the same I am pretty sure...The drive is a drive, disc is obtainable for gen 5 readily, so what makes gen 4 brain different than gen 5, just software or hardware, anyone know?

 

The LCD screen has much higher resolution on generation 5 to display much higher resolution graphic logos and maps properly. I think it would be a complete swap out.

 

Are you 100% certain of the higher resolution of the SCREEN itself ?? That makes no sense, why is it that the back up camera video is perfectly clear (also with video playback on ML dvd). I highly suspect that the gen 4 graphics to gen 5 graphics are simply a function of the firmware of the nav system itself. This even applies to my gen 3 GX, back up camera looks to have normal resolution.

 

it's a whole new unit...I believe if you search this forum...there should be more information about it. You will have to completely swap out the old Gen 4 for the new Gen 5 navigation.