Welcome to the forum. You might get better results posting this in the Mobile Electronics Section, which is all about this stuff. I would say that, if you were given the 2011 head unit it might be worth a try, but you'd have to compare the plugs on the backs of both radios to see if they are the same. If not identical, you would likely have issues. Of course, it would only possibly work if your original 2008 head unit is also a sat/nav unit, and possibly not then, as there might have been additional features added. If your 2008 car has just the basic radio, then it will likely also just have the basic wiring harness too, which won't have all the necessary plugs for it to work.